refactor: unnamed pattern _ for unused switch bindings (S1481)

dfa1 · claude · dfa1 · commit d859db00d078 · 2026-07-05T19:40:41.000+02:00
All 31 S1481 "unused local" hits were type-pattern bindings the case
never reads — `case Predicate.IsNull ignored -&gt;` and friends. The
idiomatic Java fix is the unnamed pattern `_`, not deletion (a type
pattern still needs a binding slot): `case Predicate.IsNull _ -&gt;`.
Cleaner than the `ignored` convention and Sonar-clean. Behavior
identical; full verify green including fbs-gen regeneration.

Co-Authored-By: Claude Fable 5 &lt;noreply@anthropic.com&gt;
diff --git a/calcite/src/main/java/io/github/dfa1/vortex/calcite/VortexTable.java b/calcite/src/main/java/io/github/dfa1/vortex/calcite/VortexTable.java
@@ -519,7 +519,7 @@ private static Match classifyColumn(Predicate predicate, ArrayStats s, long rowC
                     (st, v) -> compareStat(st.min(), v) >= 0, (st, v) -> compareStat(st.max(), v) < 0);
             case Predicate.Lte(var value) -> compare(s, value,
                     (st, v) -> compareStat(st.min(), v) > 0, (st, v) -> compareStat(st.max(), v) <= 0);
-            case Predicate.IsNull ignored -> {
+            case Predicate.IsNull _ -> {
                 Long nulls = s.nullCount();
                 if (nulls == null) {
                     yield Match.BOUNDARY;
@@ -529,7 +529,7 @@ private static Match classifyColumn(Predicate predicate, ArrayStats s, long rowC
                 }
                 yield nulls == 0 ? Match.OUT : Match.BOUNDARY;
             }
-            case Predicate.IsNotNull ignored -> {
+            case Predicate.IsNotNull _ -> {
                 Long nulls = s.nullCount();
                 if (nulls == null) {
                     yield Match.BOUNDARY;
@@ -539,9 +539,9 @@ private static Match classifyColumn(Predicate predicate, ArrayStats s, long rowC
                 }
                 yield nulls == rowCount ? Match.OUT : Match.BOUNDARY;
             }
-            case Predicate.Between ignored -> Match.BOUNDARY;
-            case Predicate.And ignored -> Match.BOUNDARY;
-            case Predicate.Or ignored -> Match.BOUNDARY;
+            case Predicate.Between _ -> Match.BOUNDARY;
+            case Predicate.And _ -> Match.BOUNDARY;
+            case Predicate.Or _ -> Match.BOUNDARY;
         };
     }
 
diff --git a/cli/src/main/java/io/github/dfa1/vortex/cli/FilterCommand.java b/cli/src/main/java/io/github/dfa1/vortex/cli/FilterCommand.java
@@ -179,13 +179,13 @@ private static RowPredicate columnPredicate(String col, Predicate predicate) {
                     (chunk, rowIdx) -> compareValue(chunk.column(col), rowIdx, (Comparable<?>) val) == 0;
             case Predicate.Neq(var val) ->
                     (chunk, rowIdx) -> compareValue(chunk.column(col), rowIdx, (Comparable<?>) val) != 0;
-            case Predicate.IsNull ignored -> (chunk, rowIdx) -> isRowNull(chunk.column(col), rowIdx);
-            case Predicate.IsNotNull ignored -> (chunk, rowIdx) -> !isRowNull(chunk.column(col), rowIdx);
-            case Predicate.Between ignored ->
+            case Predicate.IsNull _ -> (chunk, rowIdx) -> isRowNull(chunk.column(col), rowIdx);
+            case Predicate.IsNotNull _ -> (chunk, rowIdx) -> !isRowNull(chunk.column(col), rowIdx);
+            case Predicate.Between _ ->
                     throw new IllegalArgumentException("BETWEEN filters are not supported on the command line");
-            case Predicate.And ignored ->
+            case Predicate.And _ ->
                     throw new IllegalArgumentException("nested predicate AND is not supported on the command line");
-            case Predicate.Or ignored ->
+            case Predicate.Or _ ->
                     throw new IllegalArgumentException("nested predicate OR is not supported on the command line");
         };
     }
diff --git a/fbs-gen/src/main/java/io/github/dfa1/vortex/fbsgen/CodeGen.java b/fbs-gen/src/main/java/io/github/dfa1/vortex/fbsgen/CodeGen.java
@@ -130,7 +130,7 @@ private int emitTableField(StringBuilder sb, Ast.Field field, int vtableIndex) {
                 emitScalarTableField(sb, accessor, e.underlying(), vt, field.defaultValue().orElse(null));
                 yield vtableIndex + 1;
             }
-            case Ast.UnionDecl u -> {
+            case Ast.UnionDecl _ -> {
                 emitUnionField(sb, accessor, vt);
                 yield vtableIndex + 2;
             }
@@ -230,7 +230,7 @@ private void emitVectorField(StringBuilder sb, String accessor, Ast.FieldType el
             case Ast.EnumDecl e -> emitScalarVectorElements(sb, accessor, e.underlying(), vt);
             case Ast.TableDecl t -> emitObjectVectorElement(sb, accessor, className(t.name()), vt, 4, true);
             case Ast.StructDecl s -> emitObjectVectorElement(sb, accessor, className(s.name()), vt, registry.layoutOf(s).size(), false);
-            case Ast.UnionDecl u -> throw new FbsParseException("vectors of unions are not supported ('" + accessor + "')");
+            case Ast.UnionDecl _ -> throw new FbsParseException("vectors of unions are not supported ('" + accessor + "')");
         }
     }
 
diff --git a/reader/src/main/java/io/github/dfa1/vortex/reader/ScanIterator.java b/reader/src/main/java/io/github/dfa1/vortex/reader/ScanIterator.java
@@ -771,9 +771,9 @@ private static boolean canPrune(Predicate predicate, ArrayStats stats, long rowC
             case Predicate.Between(var lo, var hi) -> min != null && max != null
                     && (Compare.values(hi, min, ct) < 0 || Compare.values(lo, max, ct) > 0);
             // Zero nulls → no row is null → nothing can match IS NULL.
-            case Predicate.IsNull ignored -> nullCount != null && nullCount == 0;
+            case Predicate.IsNull _ -> nullCount != null && nullCount == 0;
             // Every row is null → no row is non-null → nothing can match IS NOT NULL.
-            case Predicate.IsNotNull ignored -> nullCount != null && nullCount == rowCount;
+            case Predicate.IsNotNull _ -> nullCount != null && nullCount == rowCount;
             // A conjunction is unsatisfiable if either side is; a disjunction only if both are.
             case Predicate.And(var left, var right) ->
                     canPrune(left, stats, rowCount, ct) || canPrune(right, stats, rowCount, ct);
diff --git a/reader/src/main/java/io/github/dfa1/vortex/reader/compute/PredicateEvaluator.java b/reader/src/main/java/io/github/dfa1/vortex/reader/compute/PredicateEvaluator.java
@@ -38,8 +38,8 @@ static boolean evaluate(Array array, long i, Predicate predicate) {
             case Predicate.Gte gte -> !Values.isNullAt(array, i)
                     && Compare.values(Values.valueAt(array, i), gte.value(), array.dtype()) >= 0;
             case Predicate.Between between -> evaluateBetween(array, i, between);
-            case Predicate.IsNull ignored -> Values.isNullAt(array, i);
-            case Predicate.IsNotNull ignored -> !Values.isNullAt(array, i);
+            case Predicate.IsNull _ -> Values.isNullAt(array, i);
+            case Predicate.IsNotNull _ -> !Values.isNullAt(array, i);
             case Predicate.And and -> evaluate(array, i, and.left()) && evaluate(array, i, and.right());
             case Predicate.Or or -> evaluate(array, i, or.left()) || evaluate(array, i, or.right());
         };
diff --git a/reader/src/test/java/io/github/dfa1/vortex/reader/ComputeFilteredAggregateTest.java b/reader/src/test/java/io/github/dfa1/vortex/reader/ComputeFilteredAggregateTest.java
@@ -497,8 +497,8 @@ private static boolean accepts(Predicate predicate, Reference column, int i) {
         boolean isNull = column.isNull(i);
         long v = column.values()[i];
         return switch (predicate) {
-            case Predicate.IsNull ignored -> isNull;
-            case Predicate.IsNotNull ignored -> !isNull;
+            case Predicate.IsNull _ -> isNull;
+            case Predicate.IsNotNull _ -> !isNull;
             case Predicate.Eq eq -> !isNull && v == ((Number) eq.value()).longValue();
             case Predicate.Neq neq -> !isNull && v != ((Number) neq.value()).longValue();
             case Predicate.Lt lt -> !isNull && v < ((Number) lt.value()).longValue();
diff --git a/reader/src/test/java/io/github/dfa1/vortex/reader/compute/PredicateTest.java b/reader/src/test/java/io/github/dfa1/vortex/reader/compute/PredicateTest.java
@@ -361,17 +361,17 @@ void exhaustivePatternSwitchCoversEveryVariant() {
 
         private static String label(Predicate predicate) {
             return switch (predicate) {
-                case Predicate.Eq ignored -> "eq";
-                case Predicate.Neq ignored -> "neq";
-                case Predicate.Lt ignored -> "lt";
-                case Predicate.Gt ignored -> "gt";
-                case Predicate.Lte ignored -> "lte";
-                case Predicate.Gte ignored -> "gte";
-                case Predicate.Between ignored -> "between";
-                case Predicate.IsNull ignored -> "isNull";
-                case Predicate.IsNotNull ignored -> "isNotNull";
-                case Predicate.And ignored -> "and";
-                case Predicate.Or ignored -> "or";
+                case Predicate.Eq _ -> "eq";
+                case Predicate.Neq _ -> "neq";
+                case Predicate.Lt _ -> "lt";
+                case Predicate.Gt _ -> "gt";
+                case Predicate.Lte _ -> "lte";
+                case Predicate.Gte _ -> "gte";
+                case Predicate.Between _ -> "between";
+                case Predicate.IsNull _ -> "isNull";
+                case Predicate.IsNotNull _ -> "isNotNull";
+                case Predicate.And _ -> "and";
+                case Predicate.Or _ -> "or";
             };
         }
     }
diff --git a/writer/src/main/java/io/github/dfa1/vortex/writer/VortexWriter.java b/writer/src/main/java/io/github/dfa1/vortex/writer/VortexWriter.java
@@ -911,7 +911,7 @@ private static byte[] columnSum(DType dtype, Object data) {
     private static Object zoneStatValues(DType minMaxDtype, List<byte[]> statBytes) throws IOException {
         return switch (minMaxDtype) {
             case DType.Primitive p -> statColumn(p.ptype(), statBytes);
-            case DType.Utf8 ignored -> statStringColumn(statBytes);
+            case DType.Utf8 _ -> statStringColumn(statBytes);
             default -> throw new IllegalStateException("no zone stat values for " + minMaxDtype);
         };
     }

Original file line number	Diff line number	Diff line change
`@@ -519,7 +519,7 @@ private static Match classifyColumn(Predicate predicate, ArrayStats s, long rowC`
`519`	`519`	`(st, v) -> compareStat(st.min(), v) >= 0, (st, v) -> compareStat(st.max(), v) < 0);`
`520`	`520`	`case Predicate.Lte(var value) -> compare(s, value,`
`521`	`521`	`(st, v) -> compareStat(st.min(), v) > 0, (st, v) -> compareStat(st.max(), v) <= 0);`
`522`		`- case Predicate.IsNull ignored -> {`
	`522`	`+ case Predicate.IsNull _ -> {`
`523`	`523`	`Long nulls = s.nullCount();`
`524`	`524`	`if (nulls == null) {`
`525`	`525`	`yield Match.BOUNDARY;`
`@@ -529,7 +529,7 @@ private static Match classifyColumn(Predicate predicate, ArrayStats s, long rowC`
`529`	`529`	`}`
`530`	`530`	`yield nulls == 0 ? Match.OUT : Match.BOUNDARY;`
`531`	`531`	`}`
`532`		`- case Predicate.IsNotNull ignored -> {`
	`532`	`+ case Predicate.IsNotNull _ -> {`
`533`	`533`	`Long nulls = s.nullCount();`
`534`	`534`	`if (nulls == null) {`
`535`	`535`	`yield Match.BOUNDARY;`
`@@ -539,9 +539,9 @@ private static Match classifyColumn(Predicate predicate, ArrayStats s, long rowC`
`539`	`539`	`}`
`540`	`540`	`yield nulls == rowCount ? Match.OUT : Match.BOUNDARY;`
`541`	`541`	`}`
`542`		`- case Predicate.Between ignored -> Match.BOUNDARY;`
`543`		`- case Predicate.And ignored -> Match.BOUNDARY;`
`544`		`- case Predicate.Or ignored -> Match.BOUNDARY;`
	`542`	`+ case Predicate.Between _ -> Match.BOUNDARY;`
	`543`	`+ case Predicate.And _ -> Match.BOUNDARY;`
	`544`	`+ case Predicate.Or _ -> Match.BOUNDARY;`
`545`	`545`	`};`
`546`	`546`	`}`
`547`	`547`
Original file line number	Diff line number	Diff line change
`@@ -130,7 +130,7 @@ private int emitTableField(StringBuilder sb, Ast.Field field, int vtableIndex) {`
`130`	`130`	`emitScalarTableField(sb, accessor, e.underlying(), vt, field.defaultValue().orElse(null));`
`131`	`131`	`yield vtableIndex + 1;`
`132`	`132`	`}`
`133`		`- case Ast.UnionDecl u -> {`
	`133`	`+ case Ast.UnionDecl _ -> {`
`134`	`134`	`emitUnionField(sb, accessor, vt);`
`135`	`135`	`yield vtableIndex + 2;`
`136`	`136`	`}`
`@@ -230,7 +230,7 @@ private void emitVectorField(StringBuilder sb, String accessor, Ast.FieldType el`
`230`	`230`	`case Ast.EnumDecl e -> emitScalarVectorElements(sb, accessor, e.underlying(), vt);`
`231`	`231`	`case Ast.TableDecl t -> emitObjectVectorElement(sb, accessor, className(t.name()), vt, 4, true);`
`232`	`232`	`case Ast.StructDecl s -> emitObjectVectorElement(sb, accessor, className(s.name()), vt, registry.layoutOf(s).size(), false);`
`233`		`- case Ast.UnionDecl u -> throw new FbsParseException("vectors of unions are not supported ('" + accessor + "')");`
	`233`	`+ case Ast.UnionDecl _ -> throw new FbsParseException("vectors of unions are not supported ('" + accessor + "')");`
`234`	`234`	`}`
`235`	`235`	`}`
`236`	`236`
Original file line number	Diff line number	Diff line change
`@@ -911,7 +911,7 @@ private static byte[] columnSum(DType dtype, Object data) {`
`911`	`911`	`private static Object zoneStatValues(DType minMaxDtype, List<byte[]> statBytes) throws IOException {`
`912`	`912`	`return switch (minMaxDtype) {`
`913`	`913`	`case DType.Primitive p -> statColumn(p.ptype(), statBytes);`
`914`		`- case DType.Utf8 ignored -> statStringColumn(statBytes);`
	`914`	`+ case DType.Utf8 _ -> statStringColumn(statBytes);`
`915`	`915`	`default -> throw new IllegalStateException("no zone stat values for " + minMaxDtype);`
`916`	`916`	`};`
`917`	`917`	`}`