Introduce Immutable{{List,Set}Multimap,Map,Table}BuilderPut Refaster rules (#2044)

sbsyme · web-flow · commit b46eda06611f · 2026-01-05T08:35:12.000+01:00
Resolves #2038.
diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableListMultimapRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableListMultimapRules.java
@@ -4,6 +4,7 @@
 import static com.google.common.collect.ImmutableListMultimap.toImmutableListMultimap;
 import static com.google.errorprone.refaster.ImportPolicy.STATIC_IMPORT_ALWAYS;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableMultimap;
 import com.google.common.collect.ListMultimap;
@@ -276,4 +277,28 @@ ImmutableListMultimap<K, V2> after(
       return ImmutableListMultimap.copyOf(Multimaps.transformValues(multimap, transformation));
     }
   }
+
+  /**
+   * Prefer {@link ImmutableListMultimap.Builder#put(Object, Object)} over more contrived or less
+   * efficient alternatives.
+   */
+  static final class ImmutableListMultimapBuilderPut<K, V> {
+    @BeforeTemplate
+    @SuppressWarnings("unchecked" /* Safe generic array type creation. */)
+    ImmutableListMultimap.Builder<K, V> before(
+        ImmutableListMultimap.Builder<K, V> builder, K key, V value) {
+      // XXX: Drop the `ImmutableList` case in favour of generalizing the
+      // `ExplicitArgumentEnumeration` check, or add variants for other collection types as well.
+      return Refaster.anyOf(
+          builder.put(Map.entry(key, value)),
+          builder.putAll(key, value),
+          builder.putAll(key, ImmutableList.of(value)));
+    }
+
+    @AfterTemplate
+    ImmutableListMultimap.Builder<K, V> after(
+        ImmutableListMultimap.Builder<K, V> builder, K key, V value) {
+      return builder.put(key, value);
+    }
+  }
 }
diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableMapRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableMapRules.java
@@ -422,6 +422,20 @@ ImmutableMap<K, V> after(@Repeated Map.Entry<? extends K, ? extends V> entries)
     }
   }
 
+  /** Prefer {@link ImmutableMap.Builder#put(Object, Object)} over more contrived alternatives. */
+  static final class ImmutableMapBuilderPut<K, V> {
+    @BeforeTemplate
+    ImmutableMap.Builder<K, V> before(ImmutableMap.Builder<K, V> builder, K key, V value) {
+      return Refaster.anyOf(
+          builder.put(Map.entry(key, value)), builder.putAll(ImmutableMap.of(key, value)));
+    }
+
+    @AfterTemplate
+    ImmutableMap.Builder<K, V> after(ImmutableMap.Builder<K, V> builder, K key, V value) {
+      return builder.put(key, value);
+    }
+  }
+
   // XXX: Add a rule for this:
   // Maps.transformValues(streamOfEntries.collect(groupBy(fun)), ImmutableMap::copyOf)
   // ->
diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableSetMultimapRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableSetMultimapRules.java
@@ -4,6 +4,7 @@
 import static com.google.common.collect.ImmutableSetMultimap.toImmutableSetMultimap;
 import static com.google.errorprone.refaster.ImportPolicy.STATIC_IMPORT_ALWAYS;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ImmutableSetMultimap;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Multimap;
@@ -216,4 +217,28 @@ ImmutableSetMultimap<K, V2> after(
       return ImmutableSetMultimap.copyOf(Multimaps.transformValues(multimap, transformation));
     }
   }
+
+  /**
+   * Prefer {@link ImmutableSetMultimap.Builder#put(Object, Object)} over more contrived
+   * alternatives.
+   */
+  static final class ImmutableSetMultimapBuilderPut<K, V> {
+    @BeforeTemplate
+    @SuppressWarnings("unchecked" /* Safe generic array type creation. */)
+    ImmutableSetMultimap.Builder<K, V> before(
+        ImmutableSetMultimap.Builder<K, V> builder, K key, V value) {
+      // XXX: Drop the `ImmutableSet` case in favour of generalizing the
+      // `ExplicitArgumentEnumeration` check, or add variants for other collection types as well.
+      return Refaster.anyOf(
+          builder.put(Map.entry(key, value)),
+          builder.putAll(key, value),
+          builder.putAll(key, ImmutableSet.of(value)));
+    }
+
+    @AfterTemplate
+    ImmutableSetMultimap.Builder<K, V> after(
+        ImmutableSetMultimap.Builder<K, V> builder, K key, V value) {
+      return builder.put(key, value);
+    }
+  }
 }
diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableTableRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ImmutableTableRules.java
@@ -111,4 +111,24 @@ ImmutableTable<R, C, V> after() {
       return ImmutableTable.of();
     }
   }
+
+  /**
+   * Prefer {@link ImmutableTable.Builder#put(Object, Object, Object)} over more contrived
+   * alternatives.
+   */
+  static final class ImmutableTableBuilderPut<R, C, V> {
+    @BeforeTemplate
+    ImmutableTable.Builder<R, C, V> before(
+        ImmutableTable.Builder<R, C, V> builder, R rowKey, C columnKey, V value) {
+      return Refaster.anyOf(
+          builder.put(Tables.immutableCell(rowKey, columnKey, value)),
+          builder.putAll(ImmutableTable.of(rowKey, columnKey, value)));
+    }
+
+    @AfterTemplate
+    ImmutableTable.Builder<R, C, V> after(
+        ImmutableTable.Builder<R, C, V> builder, R rowKey, C columnKey, V value) {
+      return builder.put(rowKey, columnKey, value);
+    }
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableListMultimapRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableListMultimapRulesTestInput.java
@@ -125,4 +125,12 @@ ImmutableListMultimap<String, Integer> testTransformMultimapValuesToImmutableLis
                 flatteningToImmutableListMultimap(
                     Map.Entry::getKey, e -> e.getValue().stream().map(Math::toIntExact))));
   }
+
+  ImmutableSet<ImmutableListMultimap.Builder<String, Integer>>
+      testImmutableListMultimapBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableListMultimap.<String, Integer>builder().put(Map.entry("foo", 1)),
+        ImmutableListMultimap.<String, Integer>builder().putAll("bar", 2),
+        ImmutableListMultimap.<String, Integer>builder().putAll("baz", ImmutableList.of(3)));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableListMultimapRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableListMultimapRulesTestOutput.java
@@ -98,4 +98,12 @@ ImmutableListMultimap<String, Integer> testTransformMultimapValuesToImmutableLis
         ImmutableListMultimap.copyOf(
             Multimaps.transformValues(TreeMultimap.<String, Long>create(), Math::toIntExact)));
   }
+
+  ImmutableSet<ImmutableListMultimap.Builder<String, Integer>>
+      testImmutableListMultimapBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableListMultimap.<String, Integer>builder().put("foo", 1),
+        ImmutableListMultimap.<String, Integer>builder().put("bar", 2),
+        ImmutableListMultimap.<String, Integer>builder().put("baz", 3));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableMapRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableMapRulesTestInput.java
@@ -170,4 +170,10 @@ ImmutableSet<Map<String, Integer>> testImmutableMapOfEntries() {
         Map.ofEntries(Map.entry("foo", 1)),
         Map.ofEntries(Map.entry("bar", 2), Map.entry("baz", 3)));
   }
+
+  ImmutableSet<ImmutableMap.Builder<String, Integer>> testImmutableMapBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableMap.<String, Integer>builder().put(Map.entry("foo", 1)),
+        ImmutableMap.<String, Integer>builder().putAll(ImmutableMap.of("bar", 2)));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableMapRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableMapRulesTestOutput.java
@@ -137,4 +137,10 @@ ImmutableSet<Map<String, Integer>> testImmutableMapOfEntries() {
         ImmutableMap.ofEntries(Map.entry("foo", 1)),
         ImmutableMap.ofEntries(Map.entry("bar", 2), Map.entry("baz", 3)));
   }
+
+  ImmutableSet<ImmutableMap.Builder<String, Integer>> testImmutableMapBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableMap.<String, Integer>builder().put("foo", 1),
+        ImmutableMap.<String, Integer>builder().put("bar", 2));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableSetMultimapRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableSetMultimapRulesTestInput.java
@@ -92,4 +92,11 @@ ImmutableSetMultimap<String, Integer> testTransformMultimapValuesToImmutableSetM
                 flatteningToImmutableSetMultimap(
                     Map.Entry::getKey, e -> e.getValue().stream().map(Math::toIntExact))));
   }
+
+  ImmutableSet<ImmutableSetMultimap.Builder<String, Integer>> testImmutableSetMultimapBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableSetMultimap.<String, Integer>builder().put(Map.entry("foo", 1)),
+        ImmutableSetMultimap.<String, Integer>builder().putAll("bar", 2),
+        ImmutableSetMultimap.<String, Integer>builder().putAll("baz", ImmutableSet.of(3)));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableSetMultimapRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableSetMultimapRulesTestOutput.java
@@ -73,4 +73,11 @@ ImmutableSetMultimap<String, Integer> testTransformMultimapValuesToImmutableSetM
         ImmutableSetMultimap.copyOf(
             Multimaps.transformValues(TreeMultimap.<String, Long>create(), Math::toIntExact)));
   }
+
+  ImmutableSet<ImmutableSetMultimap.Builder<String, Integer>> testImmutableSetMultimapBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableSetMultimap.<String, Integer>builder().put("foo", 1),
+        ImmutableSetMultimap.<String, Integer>builder().put("bar", 2),
+        ImmutableSetMultimap.<String, Integer>builder().put("baz", 3));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableTableRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableTableRulesTestInput.java
@@ -45,4 +45,12 @@ ImmutableTable<Integer, String, Integer> testStreamOfCellsToImmutableTable() {
   ImmutableTable<String, String, String> testImmutableTableOf() {
     return ImmutableTable.<String, String, String>builder().buildOrThrow();
   }
+
+  ImmutableSet<ImmutableTable.Builder<String, String, Integer>> testImmutableTableBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableTable.<String, String, Integer>builder()
+            .put(Tables.immutableCell("foo", "bar", 1)),
+        ImmutableTable.<String, String, Integer>builder()
+            .putAll(ImmutableTable.of("baz", "qux", 2)));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableTableRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ImmutableTableRulesTestOutput.java
@@ -42,4 +42,10 @@ ImmutableTable<Integer, String, Integer> testStreamOfCellsToImmutableTable() {
   ImmutableTable<String, String, String> testImmutableTableOf() {
     return ImmutableTable.of();
   }
+
+  ImmutableSet<ImmutableTable.Builder<String, String, Integer>> testImmutableTableBuilderPut() {
+    return ImmutableSet.of(
+        ImmutableTable.<String, String, Integer>builder().put("foo", "bar", 1),
+        ImmutableTable.<String, String, Integer>builder().put("baz", "qux", 2));
+  }
 }

Original file line number	Diff line number	Diff line change
`@@ -125,4 +125,12 @@ ImmutableListMultimap<String, Integer> testTransformMultimapValuesToImmutableLis`
`125`	`125`	`flatteningToImmutableListMultimap(`
`126`	`126`	`Map.Entry::getKey, e -> e.getValue().stream().map(Math::toIntExact))));`
`127`	`127`	`}`
	`128`	`+`
	`129`	`+ ImmutableSet<ImmutableListMultimap.Builder<String, Integer>>`
	`130`	`+ testImmutableListMultimapBuilderPut() {`
	`131`	`+ return ImmutableSet.of(`
	`132`	`+ ImmutableListMultimap.<String, Integer>builder().put(Map.entry("foo", 1)),`
	`133`	`+ ImmutableListMultimap.<String, Integer>builder().putAll("bar", 2),`
	`134`	`+ ImmutableListMultimap.<String, Integer>builder().putAll("baz", ImmutableList.of(3)));`
	`135`	`+ }`
`128`	`136`	`}`
Original file line number	Diff line number	Diff line change
`@@ -98,4 +98,12 @@ ImmutableListMultimap<String, Integer> testTransformMultimapValuesToImmutableLis`
`98`	`98`	`ImmutableListMultimap.copyOf(`
`99`	`99`	`Multimaps.transformValues(TreeMultimap.<String, Long>create(), Math::toIntExact)));`
`100`	`100`	`}`
	`101`	`+`
	`102`	`+ ImmutableSet<ImmutableListMultimap.Builder<String, Integer>>`
	`103`	`+ testImmutableListMultimapBuilderPut() {`
	`104`	`+ return ImmutableSet.of(`
	`105`	`+ ImmutableListMultimap.<String, Integer>builder().put("foo", 1),`
	`106`	`+ ImmutableListMultimap.<String, Integer>builder().put("bar", 2),`
	`107`	`+ ImmutableListMultimap.<String, Integer>builder().put("baz", 3));`
	`108`	`+ }`
`101`	`109`	`}`
Original file line number	Diff line number	Diff line change
`@@ -170,4 +170,10 @@ ImmutableSet<Map<String, Integer>> testImmutableMapOfEntries() {`
`170`	`170`	`Map.ofEntries(Map.entry("foo", 1)),`
`171`	`171`	`Map.ofEntries(Map.entry("bar", 2), Map.entry("baz", 3)));`
`172`	`172`	`}`
	`173`	`+`
	`174`	`+ ImmutableSet<ImmutableMap.Builder<String, Integer>> testImmutableMapBuilderPut() {`
	`175`	`+ return ImmutableSet.of(`
	`176`	`+ ImmutableMap.<String, Integer>builder().put(Map.entry("foo", 1)),`
	`177`	`+ ImmutableMap.<String, Integer>builder().putAll(ImmutableMap.of("bar", 2)));`
	`178`	`+ }`
`173`	`179`	`}`
Original file line number	Diff line number	Diff line change
`@@ -137,4 +137,10 @@ ImmutableSet<Map<String, Integer>> testImmutableMapOfEntries() {`
`137`	`137`	`ImmutableMap.ofEntries(Map.entry("foo", 1)),`
`138`	`138`	`ImmutableMap.ofEntries(Map.entry("bar", 2), Map.entry("baz", 3)));`
`139`	`139`	`}`
	`140`	`+`
	`141`	`+ ImmutableSet<ImmutableMap.Builder<String, Integer>> testImmutableMapBuilderPut() {`
	`142`	`+ return ImmutableSet.of(`
	`143`	`+ ImmutableMap.<String, Integer>builder().put("foo", 1),`
	`144`	`+ ImmutableMap.<String, Integer>builder().put("bar", 2));`
	`145`	`+ }`
`140`	`146`	`}`
Original file line number	Diff line number	Diff line change
`@@ -92,4 +92,11 @@ ImmutableSetMultimap<String, Integer> testTransformMultimapValuesToImmutableSetM`
`92`	`92`	`flatteningToImmutableSetMultimap(`
`93`	`93`	`Map.Entry::getKey, e -> e.getValue().stream().map(Math::toIntExact))));`
`94`	`94`	`}`
	`95`	`+`
	`96`	`+ ImmutableSet<ImmutableSetMultimap.Builder<String, Integer>> testImmutableSetMultimapBuilderPut() {`
	`97`	`+ return ImmutableSet.of(`
	`98`	`+ ImmutableSetMultimap.<String, Integer>builder().put(Map.entry("foo", 1)),`
	`99`	`+ ImmutableSetMultimap.<String, Integer>builder().putAll("bar", 2),`
	`100`	`+ ImmutableSetMultimap.<String, Integer>builder().putAll("baz", ImmutableSet.of(3)));`
	`101`	`+ }`
`95`	`102`	`}`
Original file line number	Diff line number	Diff line change
`@@ -73,4 +73,11 @@ ImmutableSetMultimap<String, Integer> testTransformMultimapValuesToImmutableSetM`
`73`	`73`	`ImmutableSetMultimap.copyOf(`
`74`	`74`	`Multimaps.transformValues(TreeMultimap.<String, Long>create(), Math::toIntExact)));`
`75`	`75`	`}`
	`76`	`+`
	`77`	`+ ImmutableSet<ImmutableSetMultimap.Builder<String, Integer>> testImmutableSetMultimapBuilderPut() {`
	`78`	`+ return ImmutableSet.of(`
	`79`	`+ ImmutableSetMultimap.<String, Integer>builder().put("foo", 1),`
	`80`	`+ ImmutableSetMultimap.<String, Integer>builder().put("bar", 2),`
	`81`	`+ ImmutableSetMultimap.<String, Integer>builder().put("baz", 3));`
	`82`	`+ }`
`76`	`83`	`}`