Fix for #1266: gather generics from placeholder references

groovy · Jun 10, 2021 · 70a96c4 · 70a96c4
1 parent 73f60f5
commit 70a96c4
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Showing 3 changed files with 82 additions and 44 deletions.
diff --git a/...e.tests.builder/src/org/eclipse/jdt/core/groovy/tests/search/GenericInferencingTests.java b/...e.tests.builder/src/org/eclipse/jdt/core/groovy/tests/search/GenericInferencingTests.java
@@ -1127,18 +1127,16 @@ public void testGetClass3() {
     @Test // GRECLIPSE-1696: Generic method type inference with @CompileStatic
     public void testMethod1() {
         String contents =
-            "import groovy.transform.CompileStatic\n" +
             "class A {\n" +
-            "    public <T> T myMethod(Class<T> claz) {\n" +
-            "        return null\n" +
-            "    }\n" +
-            "    @CompileStatic\n" +
-            "    static void main(String[] args) {\n" +
-            "        A a = new A()\n" +
-            "        def val = a.myMethod(String.class)\n" +
-            "        val.trim()\n" +
-            "    }\n" +
-            "}";
+            "  def <T> T myMethod(Class<T> claz) {\n" +
+            "  }\n" +
+            "  @groovy.transform.CompileStatic\n" +
+            "  static main(args) {\n" +
+            "    A a = new A()\n" +
+            "    def val = a.myMethod(String.class)\n" +
+            "    val.trim()\n" +
+            "  }\n" +
+            "}\n";
         int start = contents.lastIndexOf("val");
         int end = start + "val".length();
         assertType(contents, start, end, "java.lang.String");
@@ -1148,15 +1146,14 @@ public void testMethod1() {
     public void testMethod2() {
         String contents =
             "class A {\n" +
-            "    public <T> T myMethod(Class<T> claz) {\n" +
-            "        return null\n" +
-            "    }\n" +
-            "    static void main(String[] args) {\n" +
-            "        A a = new A()\n" +
-            "        def val = a.myMethod(String.class)\n" +
-            "        val.trim()\n" +
-            "    }\n" +
-            "}";
+            "  def <T> T myMethod(Class<T> claz) {\n" +
+            "  }\n" +
+            "  static main(args) {\n" +
+            "    A a = new A()\n" +
+            "    def val = a.myMethod(String.class)\n" +
+            "    val.trim()\n" +
+            "  }\n" +
+            "}\n";
         int start = contents.lastIndexOf("val");
         int end = start + "val".length();
         assertType(contents, start, end, "java.lang.String");
@@ -1165,17 +1162,15 @@ public void testMethod2() {
     @Test // Generic method without object type inference with @CompileStatic
     public void testMethod3() {
         String contents =
-            "import groovy.transform.CompileStatic\n" +
             "class A {\n" +
-            "    public <T> T myMethod(Class<T> claz) {\n" +
-            "        return null\n" +
-            "    }\n" +
-            "    @CompileStatic\n" +
-            "    def m() {\n" +
-            "        def val = myMethod(String.class)\n" +
-            "        val.trim()\n" +
-            "    }\n" +
-            "}";
+            "  def <T> T myMethod(Class<T> claz) {\n" +
+            "  }\n" +
+            "  @groovy.transform.CompileStatic\n" +
+            "  def m() {\n" +
+            "    def val = myMethod(String.class)\n" +
+            "    val.trim()\n" +
+            "  }\n" +
+            "}\n";
         int start = contents.lastIndexOf("val");
         int end = start + "val".length();
         assertType(contents, start, end, "java.lang.String");
@@ -1185,19 +1180,48 @@ public void testMethod3() {
     public void testMethod4() {
         String contents =
             "class A {\n" +
-            "    public <T> T myMethod(Class<T> claz) {\n" +
-            "        return null\n" +
-            "    }\n" +
-            "    def m() {\n" +
-            "        def val = myMethod(String.class)\n" +
-            "        val.trim()\n" +
-            "    }\n" +
-            "}";
+            "  def <T> T myMethod(Class<T> claz) {\n" +
+            "  }\n" +
+            "  def m() {\n" +
+            "    def val = myMethod(String.class)\n" +
+            "    val.trim()\n" +
+            "  }\n" +
+            "}\n";
         int start = contents.lastIndexOf("val");
         int end = start + "val".length();
         assertType(contents, start, end, "java.lang.String");
     }
 
+    @Test // https://github.com/groovy/groovy-eclipse/issues/1266
+    public void testMethod5() {
+        String contents =
+            "class C {\n" +
+            "  private <N extends Number> N m(Class<N> t) {\n" +
+            "    t.newInstance()\n" +
+            "  }\n" +
+            "  void test() {\n" +
+            "    def n = m()\n" +
+            "  }\n" +
+            "}\n";
+        assertType(contents, "m", "java.lang.Number");
+        assertType(contents, "n", "java.lang.Number");
+    }
+
+    @Test
+    public void testMethod6() {
+        String contents =
+            "class C {\n" +
+            "  private <N extends Number> N m(Class<N> t) {\n" +
+            "    t.newInstance()\n" +
+            "  }\n" +
+            "  void test() {\n" +
+            "    def n = m(Byte)\n" +
+            "  }\n" +
+            "}\n";
+        assertType(contents, "m", "java.lang.Byte");
+        assertType(contents, "n", "java.lang.Byte");
+    }
+
     @Test // GRECLIPSE-1129: Static generic method type inference with @CompileStatic
     public void testStaticMethod1() {
         String contents =

diff --git a/base/org.eclipse.jdt.groovy.core/src/org/eclipse/jdt/groovy/search/GenericsMapper.java b/base/org.eclipse.jdt.groovy.core/src/org/eclipse/jdt/groovy/search/GenericsMapper.java
@@ -64,6 +64,17 @@ public static GenericsMapper gatherGenerics(final ClassNode resolvedType) {
      * @param declaringType a type that is somewhere in {@code resolvedType}'s hierarchy used to find the target of the mapping
      */
     public static GenericsMapper gatherGenerics(final ClassNode resolvedType, final ClassNode declaringType) {
+        if (resolvedType.isArray() && declaringType.isArray()) {
+            return gatherGenerics(resolvedType.getComponentType(), declaringType.getComponentType());
+        }
+        if (declaringType.isGenericsPlaceHolder()) {
+            Map<String, ClassNode> resolved = new java.util.IdentityHashMap<>();
+            resolved.put(declaringType.getUnresolvedName(), resolvedType);
+            GenericsMapper mapper = new GenericsMapper();
+            mapper.allGenerics.add(resolved);
+            return mapper;
+        }
+
         GenericsMapper mapper = new GenericsMapper();
 
         ClassNode rCandidate = resolvedType;
@@ -261,6 +272,7 @@ protected GenericsMapper fillPlaceholders(final GenericsType[] typeParameters) {
                     if (type.getUnresolvedName().equals(tp.getName())) {
                         // replace placeholder "T" with type "Number" or "Object" or whatever
                         type = type.hasMultiRedirect() ? type.asGenericsType().getUpperBounds()[0] : type.redirect();
+                        if (type.isGenericsPlaceHolder()) type = type.getSuperClass();
                         name2Type.setValue(type);
                         break;
                     }

diff --git a/base/org.eclipse.jdt.groovy.core/src/org/eclipse/jdt/groovy/search/VariableScope.java b/base/org.eclipse.jdt.groovy.core/src/org/eclipse/jdt/groovy/search/VariableScope.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2009-2020 the original author or authors.
+ * Copyright 2009-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -624,17 +624,19 @@ void bubbleUpdates(final VariableScope defaultBranch, final VariableScope... con
 
     public static ClassNode resolveTypeParameterization(GenericsMapper mapper, ClassNode type) {
         if (mapper.hasGenerics()) {
-            GenericsType[] parameterizedTypes = GroovyUtils.getGenericsTypes(type);
-            if (parameterizedTypes.length > 0) {
-                for (int i = 0, n = parameterizedTypes.length; i < n; i += 1) {
-                    GenericsType parameterizedType = parameterizedTypes[i];
-                    ClassNode maybe = resolveTypeParameterization(mapper, parameterizedType, type);
+            GenericsType[] genericsTypes = GroovyUtils.getGenericsTypes(type);
+            int n = genericsTypes.length;
+            if (n > 0) {
+                for (int i = 0; i < n; i += 1) {
+                    ClassNode maybe = resolveTypeParameterization(mapper, genericsTypes[i], type);
                     if (maybe != type) {
                         assert n == 1;
                         type = maybe;
                         break;
                     }
                 }
+            } else if (type.isGenericsPlaceHolder()) {
+                type = mapper.findParameter(type.getUnresolvedName(), type.redirect());
             }
         }
         return type;