Merge pull request 'chore(sonar): bulk-fix production INFO analyzer warnings + skill update' (#12) from chore/sonarqube-info-prod-bulk into main

Reviewed-on: #12
2026-05-26 16:49:02 -05:00
parent 3010019dc5 c38d122d76
commit 4bb7898fe8
45 changed files with 229 additions and 235 deletions
@@ -38,29 +38,74 @@ Invoke-RestMethod -Uri "$url/api/issues/search?componentKeys=sql-utilities&resol

 `SONARQUBE_URL` / `SONARQUBE_TOKEN` are read here; `scan-sonar.ps1` reads the separate `SONAR_TOKEN` / `SONAR_HOST_URL` for the *upload* path — do not conflate them.

-## B — Cleanup loop
+## B — Cleanup loop (tiered)

 ```dot
 digraph cleanup {
-    query [label="Query open issues + facets"];
-    pick [label="Pick one rule group"];
-    edit [label="Edit code"];
-    build [label="dotnet build -c Release"];
-    test  [label="dotnet test -c Release --no-build"];
-    commit [label="git commit\nchore(sonar): … (Sxxxx)"];
-    more [label="More groups?" shape=diamond];
-    scan [label="scan-sonar.ps1"];
-    verify [label="Query API: confirm net-down"];
+    query [label="Query open issues + facets=rules"];
+    triage [label="Tier each rule:\nmechanical / judgment / API-impact"];
+    t1 [label="Tier 1 — mechanical:\nbulk-fix in one commit"];
+    t2 [label="Tier 2 — judgment:\none commit per rule, audit diff"];
+    t3 [label="Tier 3 — API-impact:\nmanual, accept !breaking or skip"];
+    build [label="dotnet build + dotnet test\nafter EACH commit"];
+    push [label="git push + open PR"];
+    ci [label="CI runs SonarScanner\non Java 17"];
+    verify [label="Re-query API:\nconfirm rule counts dropped"];

-    query -> pick -> edit -> build -> test -> commit -> more;
-    more -> pick [label="yes"];
-    more -> scan [label="no"];
-    scan -> verify;
+    query -> triage;
+    triage -> t1 -> build;
+    triage -> t2 -> build;
+    triage -> t3 -> build;
+    build -> push -> ci -> verify;
 }
 ```

-1. **Query.** Start with `severities=MAJOR,MINOR` + `facets=rules` to see what's worth fixing.
-2. **Pick a rule group.** One Sxxxx (or one tightly-related cluster) per commit, easiest first so a late blocker doesn't strand the others.
-3. **Edit → build → test.** Build must succeed; the warning count for the touched rule must drop. Tests must stay green. If a fix would degrade clarity or break a tested contract, prefer **Won't Fix on the server with a justification** over a forced code change — see [[sonarqube-wontfix-rules]] for the catalog of rules already triaged that way (S1168, S3925, CS8601, S107).
-4. **Commit.** `chore(sonar): <one-line> (Sxxxx)` — bang (`!`) if it's a breaking rename.
-5. **After all groups:** `./scan-sonar.ps1` (needs `$env:SONAR_TOKEN`). Wait ~30-60s for the CE task to finish, then re-query the issues endpoint and confirm the open MAJOR/MINOR count fell by the expected number.
+**The loop has shifted from per-rule commits to *tiered batches* once a project has more than a handful of issues left.** Use `dotnet format analyzers --diagnostics <ids> --severity info` — it runs all the Roslyn-shipped code fixers for the listed diagnostics, including `CA*`, `IDE*`, and `NUnit*`. (The `csharpsquid:Sxxxx` family from SonarAnalyzer.CSharp usually has no `dotnet format` fixer; those still need manual edits.)
+
+### Tier 1 — mechanical (one bulk commit)
+
+Rules where the fixer's rewrite is purely syntactic and can't change behavior — pile them into one `dotnet format` invocation, audit the diff for sanity, build, test, single commit:
+
+```powershell
+dotnet format analyzers Strata.SqlTools.QueryBreakdown.sln `
+  --diagnostics IDE0028 CA1825 CA1834 CA1845 CA1847 CA1860 CA1866 CA1853 CA1830 CA2249 `
+  --severity info --verbosity normal
+```
+
+Typical safe rules: `IDE0028`, `CA1825`, `CA1834`, `CA1845`, `CA1847`, `CA1853`, `CA1860`, `CA1866`, `CA2249`, `CA1830`. Some rules in this family report "no associated code fix" — they'll need manual handling separately.
+
+### Tier 2 — judgment (one commit per rule)
+
+Rules whose fixer can produce mediocre output or surprise the reader — bulk-fix but **audit before staging**:
+
+- `CA1510` — `ArgumentNullException.ThrowIfNull` rollup; always safe but voluminous, deserves its own commit.
+- `CA1822` — make-method-static; the fixer also rewrites internal callers to use type-name form. **Public methods becoming static are a binary-break for external NuGet consumers** — commit with `chore(sonar)!:` and a `BREAKING CHANGE:` footer naming each affected member, or revert those file diffs and apply only the private-helper changes.
+- `CA1861` — hoists constant array args to `static readonly` fields. The fixer's field names are sometimes cryptic (`stringArray`, `arg2`) or it emits duplicate `separator` fields in the same class. After running, rename ugly fields and dedupe collisions before committing.
+- `CA1854` — `TryGetValue`-style double-lookup elimination; trivial.
+- `CA1859` — concrete return type for perf. **No batch fixer**: edit each site manually after checking visibility. Apply only to private/internal/test; on public/protected, either revert or treat as a `!breaking` change (most cases are private helpers, so this is usually fine).
+
+### Tier 3 — manual (no fixer)
+
+`CA1806`, `CA1846`, `CA1869`, the `csharpsquid:Sxxxx` family that has no `dotnet format` fixer, and individual public-API rules that need design judgment. Edit by hand, one rule at a time. If a fix would degrade clarity or break a tested contract, prefer **server-side Won't Fix with justification** — see [[sonarqube-wontfix-rules]] for the catalog already triaged that way (S1168, S3925, CS8601, S107).
+
+### Guardrail
+
+After every commit (Tier 1, 2, or 3):
+
+```powershell
+dotnet build Strata.SqlTools.QueryBreakdown.sln -c Release --nologo
+dotnet test  Strata.SqlTools.QueryBreakdown.sln -c Release --no-build --nologo
+```
+
+Build succeeds with no new warnings beyond the baseline. Tests stay green. If either fails, fix or revert before continuing to the next tier — incremental builds can mask warning regressions, so re-run with `--no-incremental` if the warning count looks suspicious.
+
+### Scan & verify
+
+**Local `./scan-sonar.ps1` is blocked here** — the system JRE is 8 and the SonarScanner CLI requires Java 17 (`UnsupportedClassVersionError`). CI handles the scan: `.gitea/workflows/sonarqube.yml` runs `actions/setup-java@v4` with `temurin` 17 and uploads on every push and PR. So the path is **push → open PR → CI scans → re-query the API to confirm net-down**:
+
+```powershell
+$h = @{ Authorization = "Basic $b64" }
+Invoke-RestMethod -Uri "$url/api/issues/search?componentKeys=sql-utilities&resolved=false&facets=rules&ps=500" -Headers $h
+```
+
+The targeted rule IDs should each drop to 0 (or near-0 if the fixer left a few cases it couldn't batch-resolve). Commit subject style stays `chore(sonar): … (RuleId)` — bang (`!`) if the change is a deliberate breaking rename or visibility shift.
@@ -186,9 +186,9 @@ public class QueryCollectionAnalyzer
            var table = query.FromClause?.Clause?.Trim();
            if (!string.IsNullOrWhiteSpace(table))
            {
-                if (tableUsage.ContainsKey(table))
+                if (tableUsage.TryGetValue(table, out int value))
                {
-                    tableUsage[table]++;
+                    tableUsage[table] = ++value;
                }
                else
                {
@@ -221,9 +221,9 @@ public class QueryCollectionAnalyzer
            foreach (var col in columns)
            {
                var columnName = col.Trim();
-                if (columnUsage.ContainsKey(columnName))
+                if (columnUsage.TryGetValue(columnName, out int value))
                {
-                    columnUsage[columnName]++;
+                    columnUsage[columnName] = ++value;
                }
                else
                {
@@ -71,10 +71,7 @@ public class LinqQueryBreakdown : QueryBreakdown
    /// <returns>A LinqQueryBreakdown representing the query structure.</returns>
    public static LinqQueryBreakdown Analyze<T>(IQueryable<T> query)
    {
-        if (query == null)
-        {
-            throw new ArgumentNullException(nameof(query));
-        }
+        ArgumentNullException.ThrowIfNull(query);

        var breakdown = new LinqQueryBreakdown
        {
@@ -232,10 +229,7 @@ public class LinqQueryBreakdown : QueryBreakdown
    /// <returns>An InsertBreakdown representing the insert operation.</returns>
    public static Breakdowns.SqlServer.InsertBreakdown AnalyzeInsert<T>(T entity) where T : class
    {
-        if (entity == null)
-        {
-            throw new ArgumentNullException(nameof(entity));
-        }
+        ArgumentNullException.ThrowIfNull(entity);

        var breakdown = new Breakdowns.SqlServer.InsertBreakdown();
        breakdown.TableName.Clause = typeof(T).Name;
@@ -312,10 +306,7 @@ public class LinqQueryBreakdown : QueryBreakdown
    /// <returns>A DeleteBreakdown representing the delete operation.</returns>
    public static Breakdowns.SqlServer.DeleteBreakdown AnalyzeDelete<T>(Expression<Func<T, bool>> filterExpression) where T : class
    {
-        if (filterExpression == null)
-        {
-            throw new ArgumentNullException(nameof(filterExpression));
-        }
+        ArgumentNullException.ThrowIfNull(filterExpression);

        var breakdown = new Breakdowns.SqlServer.DeleteBreakdown();
        breakdown.FromClause.Clause = typeof(T).Name;
@@ -343,14 +334,8 @@ public class LinqQueryBreakdown : QueryBreakdown
        Expression<Func<T, bool>> filterExpression,
        Expression<Func<T, T>> updateExpression) where T : class
    {
-        if (filterExpression == null)
-        {
-            throw new ArgumentNullException(nameof(filterExpression));
-        }
-        if (updateExpression == null)
-        {
-            throw new ArgumentNullException(nameof(updateExpression));
-        }
+        ArgumentNullException.ThrowIfNull(filterExpression);
+        ArgumentNullException.ThrowIfNull(updateExpression);

        var breakdown = new Breakdowns.SqlServer.UpdateBreakdown();
        breakdown.TableName.Clause = typeof(T).Name;
@@ -425,10 +410,7 @@ public class LinqQueryBreakdown : QueryBreakdown
    /// <returns>A string representation of the trace analysis.</returns>
    public static string AnalyzeTrace<T>(IQueryable<T> query, string? executionContext = null) where T : class
    {
-        if (query == null)
-        {
-            throw new ArgumentNullException(nameof(query));
-        }
+        ArgumentNullException.ThrowIfNull(query);

        var lines = new List<string>
        {
@@ -580,7 +562,7 @@ public class LinqQueryBreakdown : QueryBreakdown
    /// <returns>True if SELECT contains *; otherwise, false.</returns>
    public bool SelectsAllColumns()
    {
-        return SelectClause?.Clause?.Contains("*") ?? false;
+        return SelectClause?.Clause?.Contains('*') ?? false;
    }

    /// <summary>
@@ -18,10 +18,7 @@ public static class ReverseConverterExtensions
    /// <returns>A new LinqQueryBreakdown with the same clauses.</returns>
    public static LinqQueryBreakdown ToLinqQueryBreakdown(this QueryBreakdown breakdown)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        var linq = new LinqQueryBreakdown(
            breakdown.SelectClause?.Clause ?? "*",
@@ -54,10 +51,7 @@ public static class ReverseConverterExtensions
    /// <returns>A new LinqQueryBreakdown with the same clauses.</returns>
    public static LinqQueryBreakdown ToLinqQueryBreakdown(this PostgreSqlBreakdown breakdown)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        var linq = new LinqQueryBreakdown(
            breakdown.SelectClause?.Clause ?? "*",
@@ -90,10 +84,7 @@ public static class ReverseConverterExtensions
    /// <returns>A new LinqQueryBreakdown with the same clauses.</returns>
    public static LinqQueryBreakdown ToLinqQueryBreakdown(this SnowflakeBreakdown breakdown)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        var linq = new LinqQueryBreakdown(
            breakdown.SelectClause?.Clause ?? "*",
@@ -127,10 +118,7 @@ public static class ReverseConverterExtensions
    /// <returns>A new breakdown in the target dialect format.</returns>
    public static object ConvertToDialect(this QueryBreakdown breakdown, string targetDialect)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        return targetDialect.ToLowerInvariant() switch
        {
@@ -150,10 +138,7 @@ public static class ReverseConverterExtensions
    /// <returns>A new breakdown in the target dialect format.</returns>
    public static object ConvertToDialect(this PostgreSqlBreakdown breakdown, string targetDialect)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        return targetDialect.ToLowerInvariant() switch
        {
@@ -173,10 +158,7 @@ public static class ReverseConverterExtensions
    /// <returns>A new breakdown in the target dialect format.</returns>
    public static object ConvertToDialect(this SnowflakeBreakdown breakdown, string targetDialect)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        return targetDialect.ToLowerInvariant() switch
        {
@@ -71,10 +71,7 @@ public class QueryValidator
    /// <returns>This validator for method chaining.</returns>
    public QueryValidator Validate(LinqQueryBreakdown breakdown)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        _issues.Clear();

@@ -225,7 +222,7 @@ public class QueryValidator
        }
    }

-    private void ValidateWhereClause(LinqQueryBreakdown breakdown)
+    private static void ValidateWhereClause(LinqQueryBreakdown breakdown)
    {
        // No validation needed - WHERE is optional
    }
@@ -245,12 +242,12 @@ public class QueryValidator
        }
    }

-    private void ValidateHavingClause(LinqQueryBreakdown breakdown)
+    private static void ValidateHavingClause(LinqQueryBreakdown breakdown)
    {
        // Validation delegated to ValidateGroupByClause
    }

-    private void ValidateOrderByClause(LinqQueryBreakdown breakdown)
+    private static void ValidateOrderByClause(LinqQueryBreakdown breakdown)
    {
        // No validation needed - ORDER BY is optional
    }
@@ -248,13 +248,13 @@ public class LinqExpressionVisitor : ExpressionVisitor
    {
        if (_isInWhereClause)
        {
-            _whereBuilder.Append("(");
+            _whereBuilder.Append('(');
            Visit(node.Left);

            _whereBuilder.Append($" {GetOperator(node.NodeType)} ");

            Visit(node.Right);
-            _whereBuilder.Append(")");
+            _whereBuilder.Append(')');

            return node;
        }
@@ -323,7 +323,7 @@ public class LinqExpressionVisitor : ExpressionVisitor
        return expression.ToString();
    }

-    private string GetFullMemberName(MemberExpression expression)
+    private static string GetFullMemberName(MemberExpression expression)
    {
        var parts = new Stack<string>();
        var current = expression;
@@ -354,7 +354,7 @@ public class LinqExpressionVisitor : ExpressionVisitor
        return string.Join(".", parts);
    }

-    private string GetOperator(ExpressionType nodeType)
+    private static string GetOperator(ExpressionType nodeType)
    {
        return nodeType switch
        {
@@ -260,7 +260,7 @@ public class ExpressionGenerator : IVisitor<string>
        return sb.ToString();
    }

-    private int GenerateMermaidNodes(Expression expression, StringBuilder sb, Dictionary<object, int> nodeMap, ref int nodeCounter)
+    private static int GenerateMermaidNodes(Expression expression, StringBuilder sb, Dictionary<object, int> nodeMap, ref int nodeCounter)
    {
        var currentNode = nodeCounter++;
        nodeMap[expression] = currentNode;
@@ -366,7 +366,7 @@ public class ExpressionGenerator : IVisitor<string>
        {
            return text;
        }
-        return text.Substring(0, maxLength) + "...";
+        return string.Concat(text.AsSpan(0, maxLength), "...");
    }

    #region IVisitor Implementation
@@ -583,7 +583,7 @@ public class ExpressionGenerator : IVisitor<string>
    {
        var sb = new StringBuilder();
        sb.AppendLine($"{Indent()}Function: {function.FunctionName}");
-        if (function.Arguments.Any())
+        if (function.Arguments.Length != 0)
        {
            _indentLevel++;
            sb.AppendLine($"{Indent()}Arguments:");
@@ -602,7 +602,7 @@ public class ExpressionGenerator : IVisitor<string>
    {
        var sb = new StringBuilder();
        sb.AppendLine($"{Indent()}Aggregate Function: {aggregateFunction.FunctionName}");
-        if (aggregateFunction.Arguments.Any())
+        if (aggregateFunction.Arguments.Length != 0)
        {
            _indentLevel++;
            sb.AppendLine($"{Indent()}Arguments:");
@@ -106,7 +106,7 @@ public class SimpleExpressionGenerator
        return sb.ToString();
    }

-    private string GetExpressionDescription(Expression expression)
+    private static string GetExpressionDescription(Expression expression)
    {
        var typeName = expression.GetType().Name;

@@ -37,7 +37,7 @@ public class QueryBreakdownGenerator
    /// <param name="queryBreakdown">The LINQ QueryBreakdown to visualize.</param>
    /// <param name="title">Optional title for the diagram.</param>
    /// <returns>A string containing the Mermaid flowchart showing method calls.</returns>
-    public string GenerateMethodChainDiagram(LinqQueryBreakdown queryBreakdown, string? title = null)
+    public static string GenerateMethodChainDiagram(LinqQueryBreakdown queryBreakdown, string? title = null)
    {
        var sb = new System.Text.StringBuilder();

@@ -58,7 +58,7 @@ public class SqlStatementGenerator
    /// <param name="queryBreakdown">The query breakdown containing query information.</param>
    /// <param name="title">Optional title for the diagram.</param>
    /// <returns>A string containing the Mermaid diagram markdown.</returns>
-    public string GenerateLinqPipelineDiagram(IQueryBreakdown queryBreakdown, string? title = null)
+    public static string GenerateLinqPipelineDiagram(IQueryBreakdown queryBreakdown, string? title = null)
    {
        var sb = new System.Text.StringBuilder();

@@ -177,7 +177,7 @@ public class QueryBreakdownGenerator
    /// <summary>
    /// Escapes text for Mermaid diagram labels to prevent syntax errors.
    /// </summary>
-    private string EscapeMermaidText(string text)
+    private static string EscapeMermaidText(string text)
    {
        return text
            .Replace("\"", "&quot;")
@@ -194,14 +194,14 @@ public class QueryBreakdownGenerator
    /// <summary>
    /// Truncates text to a maximum length and adds ellipsis if needed.
    /// </summary>
-    private string TruncateText(string text, int maxLength)
+    private static string TruncateText(string text, int maxLength)
    {
        if (string.IsNullOrWhiteSpace(text) || text.Length <= maxLength)
        {
            return text;
        }

-        return text.Substring(0, maxLength) + "...";
+        return string.Concat(text.AsSpan(0, maxLength), "...");
    }
 }

@@ -104,7 +104,7 @@ public class SqlStatementGenerator
    /// <summary>
    /// Escapes text for Mermaid diagram labels.
    /// </summary>
-    private string EscapeMermaidText(string text)
+    private static string EscapeMermaidText(string text)
    {
        return text
            .Replace("\"", "&quot;")
@@ -115,20 +115,20 @@ public class SqlStatementGenerator
    /// <summary>
    /// Truncates text to a maximum length.
    /// </summary>
-    private string TruncateText(string text, int maxLength)
+    private static string TruncateText(string text, int maxLength)
    {
        if (string.IsNullOrWhiteSpace(text) || text.Length <= maxLength)
        {
            return text;
        }

-        return text.Substring(0, maxLength) + "...";
+        return string.Concat(text.AsSpan(0, maxLength), "...");
    }

    /// <summary>
    /// Cleans table name for use in Mermaid diagrams.
    /// </summary>
-    private string CleanTableName(string tableName)
+    private static string CleanTableName(string tableName)
    {
        return tableName
            .Replace("[", "")
@@ -129,7 +129,7 @@ public class StatementExpressionParser : SqlServerStatementExpressionParser

                if (reader.TokenType == TokenType.String || reader.TokenType == TokenType.ColumnIdentifier)
                {
-                    columnBuilder.Append(".").Append(reader.TokenValue);
+                    columnBuilder.Append('.').Append(reader.TokenValue);
                    reader.Read();
                }
                else
@@ -191,7 +191,7 @@ public class StatementExpressionParser : SqlServerStatementExpressionParser

            if (reader.TokenType == TokenType.ColumnIdentifier || reader.TokenType == TokenType.String)
            {
-                columnBuilder.Append(".").Append(reader.TokenValue);
+                columnBuilder.Append('.').Append(reader.TokenValue);
                reader.Read();
            }
            else
@@ -113,9 +113,8 @@ public class StatementParser : SqlServerStatementParser
        // PostgreSQL-specific: Append LIMIT/OFFSET to ORDER BY if present
        var orderByClause = clauses.OrderByClause?.Clause ?? string.Empty;

-        if (clausePositions.ContainsKey(KeywordLimit))
+        if (clausePositions.TryGetValue(KeywordLimit, out int limitStart))
        {
-            var limitStart = clausePositions[KeywordLimit];
            var limitEnd = clausePositions.Values
                .Where(v => v > limitStart)
                .Order()
@@ -127,9 +126,8 @@ public class StatementParser : SqlServerStatementParser
                : $"{orderByClause} {limitClause}";
        }

-        if (clausePositions.ContainsKey(KeywordOffset))
+        if (clausePositions.TryGetValue(KeywordOffset, out int offsetStart))
        {
-            var offsetStart = clausePositions[KeywordOffset];
            var offsetEnd = clausePositions.Values
                .Where(v => v > offsetStart)
                .Order()
@@ -11,7 +11,7 @@ public class Value

    public IEnumerable<CalculationFilterGroup> FilterGroups { get; }

-    public Value() : this(string.Empty, string.Empty, new int[0], new string[0], new CalculationFilterGroup[0])
+    public Value() : this(string.Empty, string.Empty, Array.Empty<int>(), Array.Empty<string>(), Array.Empty<CalculationFilterGroup>())
    {
    }

@@ -115,7 +115,7 @@ public static class Markdown
        return ParseAtomicExpression(text);
    }

-    private static Expression? TryParseLogicalOperation(string text)
+    private static BoolExpr? TryParseLogicalOperation(string text)
    {
        foreach (var op in LogicalOperators.Keys)
        {
@@ -130,7 +130,7 @@ public static class Markdown
        return null;
    }

-    private static Expression? TryParseComparison(string text)
+    private static Comparison? TryParseComparison(string text)
    {
        foreach (var op in ComparisonOperators.Keys)
        {
@@ -50,7 +50,7 @@ public class RuleSet : IGroup
    /// </summary>
    /// <param name="group">The rule group to traverse.</param>
    /// <returns>An enumerable of all single rules found in the group.</returns>
-    private static IEnumerable<SingleRule> GetAllSingleRules(IGroup group)
+    private static List<SingleRule> GetAllSingleRules(IGroup group)
    {
        var rules = new List<SingleRule>();
        foreach (var rule in group.Rules)
@@ -55,7 +55,7 @@ public class ProcedureBreakdown : SqlServerProcedureBreakdown

        sb.Append("CALL ");
        sb.Append(ProcedureName.Clause);
-        sb.Append("(");
+        sb.Append('(');

        if (IsUsingParameters)
        {
@@ -68,7 +68,7 @@ public class ProcedureBreakdown : SqlServerProcedureBreakdown
            sb.Append(string.Join(", ", paramList));
        }

-        sb.Append(")");
+        sb.Append(')');

        return sb.ToString();
    }
@@ -141,7 +141,7 @@ public class QueryBreakdown : SqlServerQueryBreakdown

        if (parameterName.StartsWith('@'))
        {
-            return ":" + parameterName.Substring(1);
+            return string.Concat(":", parameterName.AsSpan(1));
        }

        // Add : prefix
@@ -159,7 +159,7 @@ public class QueryBreakdown : SqlServerQueryBreakdown
            if (paramName.StartsWith(':'))
            {
                // Add @param version
-                var atParam = "@" + paramName.Substring(1);
+                var atParam = string.Concat("@", paramName.AsSpan(1));
                if (!Parameters.ContainsKey(atParam))
                {
                    Parameters[atParam] = Parameters[paramName];
@@ -168,7 +168,7 @@ public class QueryBreakdown : SqlServerQueryBreakdown
            else if (paramName.StartsWith('@'))
            {
                // Add :param version
-                var colonParam = ":" + paramName.Substring(1);
+                var colonParam = string.Concat(":", paramName.AsSpan(1));
                if (!Parameters.ContainsKey(colonParam))
                {
                    Parameters[colonParam] = Parameters[paramName];
@@ -539,7 +539,7 @@ public class QueryBreakdown : SqlServerQueryBreakdown

                if (i > 0)
                {
-                    sb.Append(",");
+                    sb.Append(',');
                    sb.AppendLine();
                }

@@ -67,7 +67,7 @@ public class QueryBreakdownCollection : SqlServer.QueryBreakdownCollectionBase<Q

                if (!trimmed.EndsWith(';'))
                {
-                    sb.Append(";");
+                    sb.Append(';');
                }

                // Add spacing between statements
@@ -111,7 +111,7 @@ public class QueryBreakdownCollection : SqlServer.QueryBreakdownCollectionBase<Q
                return true;
            }

-            var specificPattern = stageName.Contains("~")
+            var specificPattern = stageName.Contains('~')
                ? $@"@~/{System.Text.RegularExpressions.Regex.Escape(stageName.TrimStart('@', '~', '/'))}/"
                : $@"@{System.Text.RegularExpressions.Regex.Escape(stageName.TrimStart('@'))}/";

@@ -182,6 +182,15 @@ public class QueryBreakdownCollection : SqlServer.QueryBreakdownCollectionBase<Q
        });
    }

+    private static readonly string[] SnowflakeFunctionNames =
+    [
+        "PARSE_JSON", "OBJECT_INSERT", "ARRAY_CONSTRUCT", "ARRAY_AGG",
+        "FLATTEN", "GET_PATH", "TRY_PARSE_JSON", "JSON_EXTRACT_PATH_TEXT",
+        "JSON_EXTRACT_PATH_WITH_DEFAULT", "HASHAGGREGATE", "LISTAGG",
+        "APPROX_COUNT_DISTINCT", "APPROX_PERCENTILE", "GREATEST", "LEAST",
+        "NULLIF", "ZEROIFNULL", "STRTOK", "SPLIT_PART", "PIVOT", "UNPIVOT"
+    ];
+
    /// <summary>
    /// Filters queries that use Snowflake functions (PARSE_JSON, OBJECT_INSERT, ARRAY, etc.).
    /// </summary>
@@ -191,17 +200,7 @@ public class QueryBreakdownCollection : SqlServer.QueryBreakdownCollectionBase<Q
        return QueryBreakdownList.Where(q =>
        {
            var sql = q.GetSql().ToUpperInvariant();
-
-            var snowflakeFunctions = new[]
-            {
-                "PARSE_JSON", "OBJECT_INSERT", "ARRAY_CONSTRUCT", "ARRAY_AGG",
-                "FLATTEN", "GET_PATH", "TRY_PARSE_JSON", "JSON_EXTRACT_PATH_TEXT",
-                "JSON_EXTRACT_PATH_WITH_DEFAULT", "HASHAGGREGATE", "LISTAGG",
-                "APPROX_COUNT_DISTINCT", "APPROX_PERCENTILE", "GREATEST", "LEAST",
-                "NULLIF", "ZEROIFNULL", "STRTOK", "SPLIT_PART", "PIVOT", "UNPIVOT"
-            };
-
-            return snowflakeFunctions.Any(func => sql.Contains(func));
+            return SnowflakeFunctionNames.Any(func => sql.Contains(func));
        });
    }

@@ -289,7 +288,7 @@ public class QueryBreakdownCollection : SqlServer.QueryBreakdownCollectionBase<Q
    /// </summary>
    private static bool UsesStageReference(QueryBreakdown query)
    {
-        return query.GetSql().Contains("@") &&
+        return query.GetSql().Contains('@') &&
               (query.GetSql().Contains("FROM @") || query.GetSql().Contains(" @"));
    }

@@ -119,9 +119,9 @@ public class StatementParser : SqlServerStatementParser
    protected override void PostProcessClauses(SqlClauses clauses, string sql, Dictionary<string, int> clausePositions)
    {
        // Snowflake-specific: Append LIMIT to ORDER BY if present
-        if (clausePositions.ContainsKey(KeywordLimit))
+        if (clausePositions.TryGetValue(KeywordLimit, out int value))
        {
-            var limitClause = sql.Substring(clausePositions[KeywordLimit]).Trim();
+            var limitClause = sql.Substring(value).Trim();
            if (clauses.OrderByClause != null)
            {
                clauses.OrderByClause.Clause = string.IsNullOrEmpty(clauses.OrderByClause.Clause)
@@ -88,10 +88,7 @@ public class SqlBreakdownCollection : ICollection<ISqlBreakdown>
    /// <exception cref="ArgumentNullException">Thrown when breakdown is null.</exception>
    public void Add(ISqlBreakdown breakdown)
    {
-        if (breakdown == null)
-        {
-            throw new ArgumentNullException(nameof(breakdown));
-        }
+        ArgumentNullException.ThrowIfNull(breakdown);

        _breakdowns.Add(breakdown);
    }
@@ -103,10 +100,7 @@ public class SqlBreakdownCollection : ICollection<ISqlBreakdown>
    /// <exception cref="ArgumentNullException">Thrown when breakdowns is null.</exception>
    public void AddRange(IEnumerable<ISqlBreakdown> breakdowns)
    {
-        if (breakdowns == null)
-        {
-            throw new ArgumentNullException(nameof(breakdowns));
-        }
+        ArgumentNullException.ThrowIfNull(breakdowns);

        _breakdowns.AddRange(breakdowns);
    }
@@ -142,10 +136,7 @@ public class SqlBreakdownCollection : ICollection<ISqlBreakdown>
    /// <exception cref="ArgumentNullException">Thrown when sqlBatch is null.</exception>
    public void ParseBatch(string sqlBatch, string? separator = null)
    {
-        if (sqlBatch == null)
-        {
-            throw new ArgumentNullException(nameof(sqlBatch));
-        }
+        ArgumentNullException.ThrowIfNull(sqlBatch);

        Clear();

@@ -85,7 +85,7 @@ public class SqlExpressionClause : SqlClause, ISqlExpressionClause
    /// </summary>
    /// <param name="clause">The clause to split.</param>
    /// <returns>An enumerable collection of individual items.</returns>
-    private static IEnumerable<string> SplitOnComma(string clause)
+    private static List<string> SplitOnComma(string clause)
    {
        var items = new List<string>();
        var current = new StringBuilder();
@@ -269,20 +269,15 @@ public static class FlatDataUtils

    public static object GetValue(this IFlatData data, string key)
    {
-        if (data == null)
-        {
-            throw new ArgumentNullException(nameof(data));
-        }
+        ArgumentNullException.ThrowIfNull(data);

-        if (!data.ContainsKey(key))
+        if (!data.TryGetValue(key, out object? rawValue))
        {
            throw new ArgumentException(
                $"The specified key is not available. Requested key: [{key}] Available keys: [{string.Join(", ", data.Keys)}]",
                nameof(key));
        }

-        var rawValue = data[key];
-
        return rawValue;
    }

@@ -41,7 +41,7 @@ public static class GuidUtils
            return Guid.Empty;
        }

-        if (value.Contains("-"))
+        if (value.Contains('-'))
        {
            // This function was called on an already valid guid
            return new Guid(value);
@@ -92,7 +92,7 @@ public static class GuidUtils
        var sb = new System.Text.StringBuilder(newguid);
        while (sb.Length < Guid.Empty.ToString().Length)
        {
-            sb.Append(sb.ToString());
+            sb.Append(sb);
        }
        newguid = sb.ToString();

@@ -114,7 +114,7 @@ public static class GuidUtils
        for (int i = 0; i < guidChars.Length; i++)
        {
            char chr = guidChars[i];
-            if (valid.IndexOf(chr) == -1 && !((chr == '-') && (i == 8 || i == 13 || i == 18 || i == 23)))
+            if (!valid.Contains(chr) && !((chr == '-') && (i == 8 || i == 13 || i == 18 || i == 23)))
            {
                guidChars[i] = valid[Math.Abs(StringUtils.GetHashCode32Bit(chr)) % valid.Length];
            }
@@ -16,7 +16,7 @@ public static partial class SqlUtils
    public static void AppendAliasColumnWithComma(StringBuilder stringBuilder, string alias, string columnName)
    {
        stringBuilder.Append(alias);
-        stringBuilder.Append(".");
+        stringBuilder.Append('.');
        stringBuilder.Append(columnName);
        stringBuilder.AppendLine(",");
    }
@@ -58,7 +58,7 @@ public static partial class SqlUtils
    {
        stringBuilder.Append("CAST(");
        stringBuilder.Append(alias);
-        stringBuilder.Append(".");
+        stringBuilder.Append('.');
        stringBuilder.Append(columnName);
        stringBuilder.Append(" AS ");
        stringBuilder.Append(dataType);
@@ -94,7 +94,7 @@ public static partial class SqlUtils
        {
            if (i > 0)
            {
-                sb.Append(",");
+                sb.Append(',');
            }

            string trimmed = columnNames[i].Trim();
@@ -42,10 +42,10 @@ public static partial class SqlUtils

        foreach (Guid g in guidList)
        {
-            sb.Append("'");
+            sb.Append('\'');
            sb.Append(g.ToString());
-            sb.Append("'");
-            sb.Append(",");
+            sb.Append('\'');
+            sb.Append(',');
        }

        return sb.ToString().Trim().TrimEnd(',');
@@ -27,7 +27,7 @@ public static partial class SqlUtils
        double.TryParse(value, out double dblValue);

        // Optimize IN if only one value
-        if (operation == FilterOperation.In && !value.Contains(","))
+        if (operation == FilterOperation.In && !value.Contains(','))
        {
            operation = FilterOperation.Equal;
        }
@@ -144,7 +144,7 @@ public static partial class SqlUtils
                }

                int lastCloseParen = sb.ToString().LastIndexOf(')');
-                filter.SqlExpression = sb.ToString().Substring(0, lastCloseParen + 1) + ")";
+                filter.SqlExpression = string.Concat(sb.ToString().AsSpan(0, lastCloseParen + 1), ")");
                break;

            case FilterOperation.NotBetween:
@@ -23,6 +23,7 @@ public static partial class SqlUtils
    public const string DATETIME_INSERT_FORMAT = "yyyyMMdd HH:mm:ss";

    private const string DEFAULT_SCHEMA = "dbo";
+    private static readonly char[] separator = new[] { ',' };

    #region SQL String Manipulation

@@ -34,7 +35,7 @@ public static partial class SqlUtils
    public static string StripColumnTableAlias(string sql)
    {
        // Break sql into words and remove "abc." from each column
-        string[] commaWords = sql.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
+        string[] commaWords = sql.Split(separator, StringSplitOptions.RemoveEmptyEntries);
        var newParts = new List<string>();

        foreach (string commaWord in commaWords)
@@ -578,7 +578,7 @@ public class QueryBreakdown : SqlBreakdownBase, IQueryBreakdown

                if (i > 0)
                {
-                    sb.Append(",");
+                    sb.Append(',');
                    sb.AppendLine();
                }

@@ -51,10 +51,7 @@ public abstract class QueryBreakdownCollectionBase<TQuery> : SqlBreakdownCollect
    /// <exception cref="ArgumentNullException">Thrown when <paramref name="queryBreakdown"/> is null.</exception>
    public void Add(TQuery queryBreakdown)
    {
-        if (queryBreakdown == null)
-        {
-            throw new ArgumentNullException(nameof(queryBreakdown));
-        }
+        ArgumentNullException.ThrowIfNull(queryBreakdown);

        QueryBreakdownList.Add(queryBreakdown);
        base.Add(queryBreakdown);
@@ -67,10 +64,7 @@ public abstract class QueryBreakdownCollectionBase<TQuery> : SqlBreakdownCollect
    /// <exception cref="ArgumentNullException">Thrown when <paramref name="queryBreakdowns"/> is null.</exception>
    public void AddRange(IEnumerable<TQuery> queryBreakdowns)
    {
-        if (queryBreakdowns == null)
-        {
-            throw new ArgumentNullException(nameof(queryBreakdowns));
-        }
+        ArgumentNullException.ThrowIfNull(queryBreakdowns);

        foreach (var breakdown in queryBreakdowns)
        {
@@ -21,6 +21,7 @@ public class StatementParser
    public const string KeywordGroupBy = "GROUP BY";
    public const string KeywordHaving = "HAVING";
    public const string KeywordOrderBy = "ORDER BY";
+    private static readonly char[] separator = new[] { '\r', '\n' };

    #endregion

@@ -50,7 +51,7 @@ public class StatementParser
        // Replace multiple spaces/tabs with single space, but preserve newlines for comment handling
        sql = Regex.Replace(sql, @"[ \t]+", " ", RegexOptions.None, RegexDefaults.MatchTimeout);
        // Remove leading/trailing whitespace from each line
-        var lines = sql.Split(new[] { '\r', '\n' }, StringSplitOptions.None);
+        var lines = sql.Split(separator, StringSplitOptions.None);
        sql = string.Join("\n", lines.Select(line => line.Trim()));
        return sql.Trim();
    }
@@ -11,7 +11,7 @@ public class QueryBreakdownRepositoryTests
 {
    private DbContext _dbContext = null!;
    private IQueryBreakdownMapper _mapper = null!;
-    private IQueryBreakdownRepository _repository = null!;
+    private QueryBreakdownRepository _repository = null!;

    [SetUp]
    public void Setup()
@@ -7,6 +7,7 @@ namespace Strata.SqlTools.LinqToSql.Tests;
 public class LinqQueryBreakdownTests
 {
    private TestDataContext _context = null!;
+    private static readonly string[] separator = new[] { "AND" };

    [SetUp]
    public void Setup()
@@ -18,7 +19,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_SimpleSelectQuery_ExtractsCorrectClauses()
    {
        // Arrange
-        var query = from user in _context.Users
+        var query = from user in TestDataContext.Users
                    select user;

        // Act
@@ -34,7 +35,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_WhereClause_ExtractsCondition()
    {
        // Arrange
-        var query = from user in _context.Users
+        var query = from user in TestDataContext.Users
                    where user.Age > 21
                    select user;

@@ -51,7 +52,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_SelectWithProjection_ExtractsSelectedFields()
    {
        // Arrange
-        var query = from user in _context.Users
+        var query = from user in TestDataContext.Users
                    select new { user.Id, user.Name };

        // Act
@@ -67,7 +68,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_OrderByClause_ExtractsOrdering()
    {
        // Arrange
-        var query = from user in _context.Users
+        var query = from user in TestDataContext.Users
                    orderby user.Name
                    select user;

@@ -83,7 +84,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_MethodSyntax_ExtractsCorrectClauses()
    {
        // Arrange
-        var query = _context.Users
+        var query = TestDataContext.Users
            .Where(u => u.Age > 18)
            .OrderBy(u => u.Name)
            .Select(u => new { u.Id, u.Name });
@@ -101,7 +102,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_MethodSyntax_TracksMethodChain()
    {
        // Arrange
-        var query = _context.Users
+        var query = TestDataContext.Users
            .Where(u => u.Age > 18)
            .OrderBy(u => u.Name)
            .Select(u => u.Name);
@@ -120,7 +121,7 @@ public class LinqQueryBreakdownTests
    public void GetQuerySummary_ReturnsFormattedString()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 21);
+        var query = TestDataContext.Users.Where(u => u.Age > 21);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -137,7 +138,7 @@ public class LinqQueryBreakdownTests
    public void GetMethodChain_ReturnsMethodSequence()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 18).OrderBy(u => u.Name);
+        var query = TestDataContext.Users.Where(u => u.Age > 18).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -153,7 +154,7 @@ public class LinqQueryBreakdownTests
    public void TryAnalyze_ValidQuery_ReturnsTrue()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 21);
+        var query = TestDataContext.Users.Where(u => u.Age > 21);

        // Act
        var success = LinqQueryBreakdown.TryAnalyze(query, out var breakdown, out var error);
@@ -182,7 +183,7 @@ public class LinqQueryBreakdownTests
    public void Analyze_ComplexQuery_HandlesCombinedClauses()
    {
        // Arrange
-        var query = from user in _context.Users
+        var query = from user in TestDataContext.Users
                    where user.Age > 21 && user.IsActive
                    orderby user.Name descending
                    select new { user.Id, user.Name, user.Email };
@@ -205,7 +206,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndModify_AddWhereClause_GeneratesUpdatedSql()
    {
        // Arrange - Analyze an existing LINQ query
-        var originalQuery = _context.Users.Where(u => u.Age > 21);
+        var originalQuery = TestDataContext.Users.Where(u => u.Age > 21);
        var breakdown = LinqQueryBreakdown.Analyze(originalQuery);

        // Act - Add additional filter using breakdown
@@ -222,7 +223,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndModify_ChangeSelectClause_GeneratesNewProjection()
    {
        // Arrange - Analyze query with projection
-        var originalQuery = _context.Users.Select(u => new { u.Id, u.Name });
+        var originalQuery = TestDataContext.Users.Select(u => new { u.Id, u.Name });
        var breakdown = LinqQueryBreakdown.Analyze(originalQuery);

        // Act - Modify the SELECT clause
@@ -243,7 +244,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndModify_CloneAndExtend_CreatesIndependentQuery()
    {
        // Arrange - Analyze base query
-        var baseQuery = _context.Users.Where(u => u.Age > 18);
+        var baseQuery = TestDataContext.Users.Where(u => u.Age > 18);
        var baseBreakdown = LinqQueryBreakdown.Analyze(baseQuery);

        // Act - Clone and extend
@@ -267,10 +268,10 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndCompose_MultipleQueries_CreatesUnionScenario()
    {
        // Arrange - Analyze two different queries
-        var activeUsersQuery = _context.Users.Where(u => u.IsActive);
+        var activeUsersQuery = TestDataContext.Users.Where(u => u.IsActive);
        var activeBreakdown = LinqQueryBreakdown.Analyze(activeUsersQuery);

-        var recentUsersQuery = _context.Users.Where(u => u.Age < 25);
+        var recentUsersQuery = TestDataContext.Users.Where(u => u.Age < 25);
        var recentBreakdown = LinqQueryBreakdown.Analyze(recentUsersQuery);

        // Act - Get SQL for both (could be used in UNION scenario)
@@ -287,7 +288,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndBuildFilter_IncrementallyAddConditions_BuildsComplexFilter()
    {
        // Arrange - Start with simple query
-        var query = _context.Users;
+        var query = TestDataContext.Users;
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - Incrementally add filter conditions (simulating filter builder UI)
@@ -303,7 +304,7 @@ public class LinqQueryBreakdownTests
        Assert.That(filterSql, Does.Contain("IsActive = 1"));

        // Should have multiple AND conditions
-        var andCount = filterSql.Split(new[] { "AND" }, StringSplitOptions.None).Length - 1;
+        var andCount = filterSql.Split(separator, StringSplitOptions.None).Length - 1;
        Assert.That(andCount, Is.GreaterThanOrEqualTo(2));
    }

@@ -311,7 +312,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndPaginate_AddOrderAndLimits_CreatesPaginatedQuery()
    {
        // Arrange - Analyze base query
-        var query = _context.Users.Where(u => u.IsActive);
+        var query = TestDataContext.Users.Where(u => u.IsActive);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - Add pagination (ORDER BY required for consistent pagination)
@@ -335,7 +336,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndGenerateReport_ExtractQueryMetrics_ProvidesAnalytics()
    {
        // Arrange - Complex query to analyze
-        var query = _context.Users
+        var query = TestDataContext.Users
            .Where(u => u.Age > 21)
            .Where(u => u.IsActive)
            .OrderBy(u => u.Name)
@@ -364,7 +365,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndOptimize_RemoveSelectStar_ImprovedProjection()
    {
        // Arrange - Analyze query with SELECT *
-        var query = _context.Users.Where(u => u.IsActive);
+        var query = TestDataContext.Users.Where(u => u.IsActive);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Verify it initially has SELECT *
@@ -390,10 +391,10 @@ public class LinqQueryBreakdownTests
    public void AnalyzeMultipleQueries_CompareAndMerge_CreatesCompositeQuery()
    {
        // Arrange - Analyze two related queries
-        var usersQuery = _context.Users.Where(u => u.Age > 21);
+        var usersQuery = TestDataContext.Users.Where(u => u.Age > 21);
        var usersBreakdown = LinqQueryBreakdown.Analyze(usersQuery);

-        var activeQuery = _context.Users.Where(u => u.IsActive);
+        var activeQuery = TestDataContext.Users.Where(u => u.IsActive);
        var activeBreakdown = LinqQueryBreakdown.Analyze(activeQuery);

        // Act - Merge conditions from both queries
@@ -416,7 +417,7 @@ public class LinqQueryBreakdownTests
    public void AnalyzeAndDocument_GenerateQueryDocumentation_CreatesReadableOutput()
    {
        // Arrange - Analyze a business query
-        var query = _context.Orders
+        var query = TestDataContext.Orders
            .Where(o => o.Amount > 1000)
            .Where(o => o.OrderDate > DateTime.Now.AddDays(-30))
            .OrderBy(o => o.OrderDate);
@@ -451,8 +452,8 @@ public class LinqQueryBreakdownTests
 // Test data context and entities
 public class TestDataContext
 {
-    public IQueryable<User> Users => new List<User>().AsQueryable();
-    public IQueryable<Order> Orders => new List<Order>().AsQueryable();
+    public static IQueryable<User> Users => new List<User>().AsQueryable();
+    public static IQueryable<Order> Orders => new List<Order>().AsQueryable();
 }

 public class User
@@ -488,7 +489,7 @@ public class GetQueryTests
    public void GetQuery_LinqBreakdown_ReturnsNullByDefault()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 18);
+        var query = TestDataContext.Users.Where(u => u.Age > 18);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - GetQuery returns null because LinqQueryBreakdown needs the original provider
@@ -515,7 +516,7 @@ public class GetQueryTests
    public void GetQuery_MultipleBreakdownTypes_AllReturnNull()
    {
        // Arrange
-        var linqBreakdown = LinqQueryBreakdown.Analyze(_context.Users);
+        var linqBreakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users);
        var sqlBreakdown = new QueryBreakdown("*", "Users");

        // Act
@@ -710,7 +711,7 @@ public class GetQueryTests
    public void AnalyzeTrace_WithValidQuery_ReturnsTraceString()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 18);
+        var query = TestDataContext.Users.Where(u => u.Age > 18);

        // Act
        var trace = LinqQueryBreakdown.AnalyzeTrace(query);
@@ -726,7 +727,7 @@ public class GetQueryTests
    public void AnalyzeTrace_WithExecutionContext_IncludesContextInTrace()
    {
        // Arrange
-        var query = _context.Users;
+        var query = TestDataContext.Users;
        const string context = "Initial Load";

        // Act
@@ -754,7 +755,7 @@ public class GetQueryTests
    public void ConvertToSqlServerBreakdown_CopiesAllClauses()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
+        var query = TestDataContext.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -772,7 +773,7 @@ public class GetQueryTests
    public void ConvertToPostgreSqlBreakdown_CopiesAllClauses()
    {
        // Arrange
-        var query = _context.Users
+        var query = TestDataContext.Users
            .Where(u => u.IsActive)
            .OrderBy(u => u.Name)
            .Select(u => new { u.Id, u.Name });
@@ -793,7 +794,7 @@ public class GetQueryTests
    public void ConvertToSnowflakeBreakdown_CopiesAllClauses()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
+        var query = TestDataContext.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -827,7 +828,7 @@ public class GetQueryTests
    public void ConvertToPostgreSqlBreakdown_WithComplexQuery_CopieAllClauses()
    {
        // Arrange
-        var query = _context.Users
+        var query = TestDataContext.Users
            .Where(u => u.IsActive && u.Age >= 18)
            .OrderByDescending(u => u.Age);

@@ -848,7 +849,7 @@ public class GetQueryTests
    public void ConvertToSnowflakeBreakdown_PreservesAllClauseInformation()
    {
        // Arrange
-        var breakdown = LinqQueryBreakdown.Analyze(_context.Users.OrderBy(u => u.Name));
+        var breakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users.OrderBy(u => u.Name));

        // Act
        var snowflakeBreakdown = breakdown.ConvertToSnowflakeBreakdown();
@@ -862,7 +863,7 @@ public class GetQueryTests
    public void ConvertToSqlServerBreakdown_InstancesAreIndependent()
    {
        // Arrange
-        var breakdown = LinqQueryBreakdown.Analyze(_context.Users.Where(u => u.Age > 21));
+        var breakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users.Where(u => u.Age > 21));
        var sqlServerBreakdown = breakdown.ConvertToSqlServerBreakdown();

        // Act - Modify the SQL Server breakdown
@@ -876,7 +877,7 @@ public class GetQueryTests
    public void ConvertChainMultipleTimes_EachConversionIndependent()
    {
        // Arrange
-        var breakdown = LinqQueryBreakdown.Analyze(_context.Users.OrderBy(u => u.Name));
+        var breakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users.OrderBy(u => u.Name));

        // Act
        var sqlServer1 = breakdown.ConvertToSqlServerBreakdown();
@@ -20,7 +20,7 @@ public class QueryBreakdownGeneratorTests
    public void GenerateMermaidDiagram_SimpleLinqQuery_GeneratesValidMermaid()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 21);
+        var query = TestDataContext.Users.Where(u => u.Age > 21);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -39,14 +39,14 @@ public class QueryBreakdownGeneratorTests
    public void GenerateMethodChainDiagram_WithMethodCalls_ShowsChain()
    {
        // Arrange
-        var query = _context.Users
+        var query = TestDataContext.Users
            .Where(u => u.Age > 18)
            .OrderBy(u => u.Name)
            .Select(u => new { u.Id, u.Name });
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
-        var result = _generator.GenerateMethodChainDiagram(breakdown, "Method Chain");
+        var result = QueryBreakdownGenerator.GenerateMethodChainDiagram(breakdown, "Method Chain");

        // Assert
        Assert.That(result, Does.Contain("```mermaid"));
@@ -66,7 +66,7 @@ public class QueryBreakdownGeneratorTests
        var breakdown = new LinqQueryBreakdown("*", "Users");

        // Act
-        var result = _generator.GenerateMethodChainDiagram(breakdown);
+        var result = QueryBreakdownGenerator.GenerateMethodChainDiagram(breakdown);

        // Assert
        Assert.That(result, Does.Contain("IQueryable"));
@@ -77,7 +77,7 @@ public class QueryBreakdownGeneratorTests
    public void GenerateCombinedDiagram_IncludesBothDiagrams()
    {
        // Arrange
-        var query = _context.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
+        var query = TestDataContext.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -95,7 +95,7 @@ public class QueryBreakdownGeneratorTests
    public void GenerateMermaidDiagram_WithProjection_ShowsSelectedFields()
    {
        // Arrange
-        var query = _context.Users.Select(u => new { u.Id, u.Name, u.Email });
+        var query = TestDataContext.Users.Select(u => new { u.Id, u.Name, u.Email });
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -110,7 +110,7 @@ public class QueryBreakdownGeneratorTests
    public void GenerateMermaidDiagram_NullTitle_GeneratesWithoutTitle()
    {
        // Arrange
-        var query = _context.Users;
+        var query = TestDataContext.Users;
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
@@ -125,7 +125,7 @@ public class QueryBreakdownGeneratorTests
 // Test data context
 public class TestDataContext
 {
-    public IQueryable<User> Users => new List<User>().AsQueryable();
+    public static IQueryable<User> Users => new List<User>().AsQueryable();
 }

 public class User
@@ -21,7 +21,7 @@ public class SqlStatementGeneratorTests
        var query = new LinqQueryBreakdown("*", "Users");

        // Act
-        var result = _generator.GenerateLinqPipelineDiagram(query, "User Query Pipeline");
+        var result = SqlStatementGenerator.GenerateLinqPipelineDiagram(query, "User Query Pipeline");

        // Assert
        Assert.That(result, Does.Contain("```mermaid"));
@@ -42,7 +42,7 @@ public class SqlStatementGeneratorTests
        query.AddWhereClause("Age > 21");

        // Act
-        var result = _generator.GenerateLinqPipelineDiagram(query);
+        var result = SqlStatementGenerator.GenerateLinqPipelineDiagram(query);

        // Assert
        Assert.That(result, Does.Contain("Where Predicate"));
@@ -57,7 +57,7 @@ public class SqlStatementGeneratorTests
        var query = new LinqQueryBreakdown("Id, Name, Email", "Users");

        // Act
-        var result = _generator.GenerateLinqPipelineDiagram(query);
+        var result = SqlStatementGenerator.GenerateLinqPipelineDiagram(query);

        // Assert
        Assert.That(result, Does.Contain("Select Projection"));
@@ -72,7 +72,7 @@ public class SqlStatementGeneratorTests
        var query = new LinqQueryBreakdown("*", "Users");

        // Act
-        var result = _generator.GenerateLinqPipelineDiagram(query, null);
+        var result = SqlStatementGenerator.GenerateLinqPipelineDiagram(query, null);

        // Assert
        Assert.That(result, Does.Not.Contain("###"));
@@ -513,7 +513,7 @@ public class QueryBreakdownTests

        // Assert
        // Find the UserId parameter value
-        var userIdKey = merged.Keys.FirstOrDefault(k => k.Contains("UserId") && !k.Contains("$"));
+        var userIdKey = merged.Keys.FirstOrDefault(k => k.Contains("UserId") && !k.Contains('$'));
        Assert.That(userIdKey, Is.Not.Null);
        Assert.That(merged[userIdKey], Is.EqualTo(123)); // Main query value, not CTE value
    }
@@ -559,9 +559,9 @@ public class QueryBreakdownTests
        var merged = mainQuery.GetMergedParameters();

        // Assert
-        var dateKey = merged.Keys.FirstOrDefault(k => k.Contains("CreatedDate") && !k.Contains("$"));
-        var boolKey = merged.Keys.FirstOrDefault(k => k.Contains("IsActive") && !k.Contains("$"));
-        var doubleKey = merged.Keys.FirstOrDefault(k => k.Contains("Threshold") && !k.Contains("$"));
+        var dateKey = merged.Keys.FirstOrDefault(k => k.Contains("CreatedDate") && !k.Contains('$'));
+        var boolKey = merged.Keys.FirstOrDefault(k => k.Contains("IsActive") && !k.Contains('$'));
+        var doubleKey = merged.Keys.FirstOrDefault(k => k.Contains("Threshold") && !k.Contains('$'));

        Assert.That(dateKey, Is.Not.Null);
        Assert.That(merged[dateKey], Is.TypeOf<DateTime>());
@@ -133,7 +133,7 @@ public class TestRuleInput

    public string? ImGoingToMakeThisNull { get; set; } = null;

-    public TestRuleDetail[] Details { get; set; } = { };
+    public TestRuleDetail[] Details { get; set; } = Array.Empty<TestRuleDetail>();
 }

 public class TestRuleDetail
@@ -148,7 +148,7 @@ public class Tests
        return result;
    }

-    static System.Linq.Expressions.Expression StartsWith(System.Linq.Expressions.Expression expression, string value)
+    static MethodCallExpression StartsWith(System.Linq.Expressions.Expression expression, string value)
    {
        return StartsWith(expression, LinqExpression.Constant(value));
    }
@@ -98,6 +98,8 @@ public class QueryBreakdownTests
        Assert.That(sql, Does.Contain("ORDER BY"));
    }

+    private static readonly char[] separator = new[] { '\r', '\n' };
+
    [Test]
    public void GetSql_WithSingleWithClause_UsesSnowflakeIndentation()
    {
@@ -114,7 +116,7 @@ public class QueryBreakdownTests
        Assert.That(sql, Does.Contain("WITH"));
        Assert.That(sql, Does.Contain("PRODUCT_SUMMARY AS ("));
        // Verify 4-space Snowflake indentation
-        var lines = sql.Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);
+        var lines = sql.Split(separator, StringSplitOptions.RemoveEmptyEntries);
        var indentedLines = lines.Where(l => l.StartsWith("    ")).ToList();
        Assert.That(indentedLines.Count, Is.GreaterThan(0));
    }
@@ -1118,7 +1120,7 @@ public class QueryBreakdownTests
        _ = baseQueryBreakdown.GetSql();

        // Assert - Snowflake should use 4-space indent, base uses 5-space
-        var snowflakeLines = snowflakeSql.Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);
+        var snowflakeLines = snowflakeSql.Split(separator, StringSplitOptions.RemoveEmptyEntries);
        var snowflakeIndentedLines = snowflakeLines.Where(l => l.StartsWith("    ") && !l.StartsWith("     ")).ToList();
        Assert.That(snowflakeIndentedLines.Count, Is.GreaterThan(0), "Snowflake should use 4-space indentation");
    }
@@ -1322,7 +1324,7 @@ public class QueryBreakdownTests
        Assert.That(snowflakeSql, Does.Contain("WHERE"));
        Assert.That(snowflakeSql, Does.Contain("ORDER BY"));
        // Verify Snowflake-style formatting (4-space indentation)
-        var lines = snowflakeSql.Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);
+        var lines = snowflakeSql.Split(separator, StringSplitOptions.RemoveEmptyEntries);
        var indentedLines = lines.Where(l => l.StartsWith("    ")).ToList();
        Assert.That(indentedLines.Count, Is.GreaterThan(0), "Should have Snowflake-style indentation");
    }
@@ -5,6 +5,8 @@ namespace Strata.SqlTools.SqlBreakdown.Tests.ExpressionTests;
 [TestFixture]
 public class ExpressionFactoryFilterTests : ExpressionTestsBase
 {
+    private static readonly string[] values = new[] { "FY2019", "FY2020", "FY2021", "FY2022" };
+
    private static IEnumerable<TestCaseData> FilterTestCases()
    {
        var dischargeDate = DateTime.Now.Date.AddMonths(1);
@@ -16,7 +18,7 @@ public class ExpressionFactoryFilterTests : ExpressionTestsBase
        ).SetName("ListFilterContinuous_{m}");

        yield return new TestCaseData(
-            new Filter(4, FilterType.List, new[] { "FY2019", "FY2020", "FY2021", "FY2022" }, Array.Empty<FilterCondition>(), DatePart.FiscalYear, false, 0, 0),
+            new Filter(4, FilterType.List, values, Array.Empty<FilterCondition>(), DatePart.FiscalYear, false, 0, 0),
            "(DEPT.DISCHARGE_DATE >= '2018-07-01' AND DEPT.DISCHARGE_DATE < '2019-07-01') OR \n(DEPT.DISCHARGE_DATE >= '2019-07-01' AND DEPT.DISCHARGE_DATE < '2020-07-01') OR \n(DEPT.DISCHARGE_DATE >= '2020-07-01' AND DEPT.DISCHARGE_DATE < '2021-07-01') OR \n(DEPT.DISCHARGE_DATE >= '2021-07-01' AND DEPT.DISCHARGE_DATE < '2022-07-01')"
        ).SetName("DateListFilterFiscalYear_{m}");

@@ -31,7 +33,7 @@ public class ExpressionFactoryFilterTests : ExpressionTestsBase
        ).SetName("CalendarFilter_{m}");

        yield return new TestCaseData(
-            new Filter(4, FilterType.Timeframe, new object[] { }, Array.Empty<FilterCondition>(), DatePart.Month, false, 1, 3),
+            new Filter(4, FilterType.Timeframe, Array.Empty<object>(), Array.Empty<FilterCondition>(), DatePart.Month, false, 1, 3),
            $"DEPT.DISCHARGE_DATE >= '{startOfCurrentMonth:yyyy-MM-dd}' AND DEPT.DISCHARGE_DATE < '{startOfEndMonth:yyyy-MM-dd}'"
        ).SetName("TimeframeFilter_{m}");
    }
@@ -29,6 +29,8 @@ public class ExpressionObjectTests : ExpressionTestsBase
        Assert.That(paramExp.ParameterName, Is.EqualTo("MY_PARAM"));
    }

+    private static readonly string[] NotInValues = new[] { "value1", "value2", "value3" };
+
    private static IEnumerable<TestCaseData> ComparisonExpressionTestCases()
    {
        yield return new TestCaseData("GreaterThanOrEqual", 250, typeof(GreaterThanOrEqualToExpression))
@@ -40,7 +42,7 @@ public class ExpressionObjectTests : ExpressionTestsBase
        yield return new TestCaseData("Equals", "TestDept", typeof(EqualToExpression))
            .SetName("Equals_{m}");

-        yield return new TestCaseData("NotIn", new[] { "value1", "value2", "value3" }, typeof(NotInExpression))
+        yield return new TestCaseData("NotIn", NotInValues, typeof(NotInExpression))
            .SetName("NotIn_{m}");

        yield return new TestCaseData("Like", "%pattern%", typeof(LikeExpression))
@@ -57,7 +57,7 @@ public abstract class ExpressionTestsBase
    /// Executes an expression test case with arrange, act, and assert phases.
    /// </summary>
    /// <param name="testCase">The test case to execute.</param>
-    protected void ExecuteExpressionTest(ExpressionTestCase testCase)
+    protected static void ExecuteExpressionTest(ExpressionTestCase testCase)
    {
        // Arrange
        var visitor = new CommandVisitor();
@@ -243,12 +243,14 @@ public class QueryBreakdownExtensionsTests
        Assert.That(query.WithClauses[1].TableName, Is.EqualTo("recent_orders"));
    }

+    private static readonly string[] columns = new[] { "id", "name", "email" };
+
    [Test]
    public void WithCte_WithColumnList_AddsCtesWithColumns()
    {
        // Arrange & Act
        var query = new QueryBreakdown()
-            .WithCte("active_users", new[] { "id", "name", "email" }, cte => cte
+            .WithCte("active_users", columns, cte => cte
                .Select("user_id, user_name, user_email")
                .From("users")
                .Where("status = 'active'"))
@@ -174,7 +174,7 @@ public class RecursiveCTETests
        var merged = mainQuery.GetMergedParameters();

        // Assert
-        var statusKey = merged.Keys.FirstOrDefault(k => k.Contains("Status") && !k.Contains("@") && !k.Contains("$"));
+        var statusKey = merged.Keys.FirstOrDefault(k => k.Contains("Status") && !k.Contains('@') && !k.Contains('$'));
        Assert.That(statusKey, Is.Not.Null);
        Assert.That(merged[statusKey], Is.EqualTo("active"), "Main query parameter should take precedence");
    }