Fix bm25 parameter count lint

Closes #3292
simolus3 · Oct 24, 2024 · 5c2af78 · 5c2af78
1 parent 6c1edb7
commit 5c2af78
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Showing 4 changed files with 52 additions and 7 deletions.
diff --git a/sqlparser/CHANGELOG.md b/sqlparser/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.39.2-dev
+
+- Fix false-positive lint for a parameter count mismatch on `bm25()`.
+
 ## 0.39.1
 
 - Improve recovery in parser when encountering syntax errors.

diff --git a/sqlparser/lib/src/engine/module/fts5.dart b/sqlparser/lib/src/engine/module/fts5.dart
@@ -153,8 +153,13 @@ class _Fts5Functions with ArgumentCountLinter implements FunctionHandler {
 
     switch (call.name) {
       case 'bm25':
-        // bm25(fts_table)
-        return const ResolveResult.unknown();
+        // bm25(fts_table, weights...)
+        if (argumentIndex == 0) {
+          return const ResolveResult.unknown();
+        } else {
+          return const ResolveResult(ResolvedType(type: BasicType.int));
+        }
+
       case 'highlight':
         // highlight(fts_table, column_index, text_before, text_after)
         if (argumentIndex == 1) {
@@ -183,7 +188,6 @@ class _Fts5Functions with ArgumentCountLinter implements FunctionHandler {
       case 'bm25':
         return const ResolveResult(ResolvedType(type: BasicType.real));
       case 'highlight':
-        return const ResolveResult(ResolvedType(type: BasicType.text));
       case 'snippet':
         return const ResolveResult(ResolvedType(type: BasicType.text));
     }
@@ -193,7 +197,6 @@ class _Fts5Functions with ArgumentCountLinter implements FunctionHandler {
   @override
   int? argumentCountFor(String function) {
     return const {
-      'bm25': 1,
       'highlight': 4,
       'snippet': 6,
     }[function];
@@ -212,9 +215,10 @@ class _Fts5Functions with ArgumentCountLinter implements FunctionHandler {
     }
 
     final args = (call.parameters as ExprFunctionParameters).parameters;
-    final expectedArgCount = argumentCountFor(call.name.toLowerCase());
+    final calledFunction = call.name.toLowerCase();
+    final expectedArgCount = argumentCountFor(calledFunction);
 
-    if (expectedArgCount != args.length) {
+    if (expectedArgCount != null && expectedArgCount != args.length) {
       reportArgumentCountMismatch(call, context, expectedArgCount, args.length);
       return;
     }
@@ -231,6 +235,20 @@ class _Fts5Functions with ArgumentCountLinter implements FunctionHandler {
         message: 'Expected an fts5 table name here',
         type: AnalysisErrorType.other,
       ));
+    } else if (calledFunction == 'bm25') {
+      // The bm25 function can use (table, weights...) parameters, but there
+      // shouldn't be more weights than columns.
+      final source = firstResolved.source as _Fts5TableColumn;
+      if (source.table case final table?) {
+        if (args.length > table.resultColumns.length + 1) {
+          context.reportError(AnalysisError(
+            relevantNode: call,
+            message: 'Superfluous weight columns (there are only '
+                '${table.resultColumns.length} columns on the table).',
+            type: AnalysisErrorType.other,
+          ));
+        }
+      }
     }
   }
 }

diff --git a/sqlparser/pubspec.yaml b/sqlparser/pubspec.yaml
@@ -1,6 +1,6 @@
 name: sqlparser
 description: Parses sqlite statements and performs static analysis on them
-version: 0.39.1
+version: 0.39.2
 homepage: https://github.com/simolus3/drift/tree/develop/sqlparser
 repository: https://github.com/simolus3/drift
 #homepage: https://drift.simonbinder.eu/

diff --git a/sqlparser/test/engine/module/fts5_test.dart b/sqlparser/test/engine/module/fts5_test.dart
@@ -240,6 +240,16 @@ void main() {
         ],
       );
     });
+
+    test('for bm25', () {
+      checkVarTypes(
+        'SELECT bm25(fts, ?, ?) FROM fts;',
+        [
+          BasicType.int,
+          BasicType.int,
+        ],
+      );
+    });
   });
 
   group('error reporting', () {
@@ -281,6 +291,19 @@ void main() {
         ],
       );
     });
+
+    test('with too many weights in bm25', () {
+      final result =
+          engine.analyze('SELECT bm25(foo, 0.5, 0.6, 0.1) FROM foo;');
+
+      expect(
+        result.errors,
+        [
+          hasMessage(
+              'Superfluous weight columns (there are only 2 columns on the table).')
+        ],
+      );
+    });
   });
 
   test('does not include rank and table columns in result', () {