fix(java): type generation code-gen issues (#3735)

Some collection validations were emitted twice, due to a bad merge
conflict resolution.

Additionally, in certain cases where overrides are being emitted for
type unions, the type checking code made unnecessary assertions, some of
which ending up being prohibited by the compiler.



---

By submitting this pull request, I confirm that my contribution is made under the terms of the [Apache 2.0 license].

[Apache 2.0 license]: https://www.apache.org/licenses/LICENSE-2.0

.github/workflows/main.yml

@@ -39,8 +39,8 @@ jobs:
       - name: Set up Java 8
         uses: actions/setup-java@v3
         with:
-          java-version: '8'
           distribution: 'zulu'
+          java-version: '8'
       - name: Set up Node 14
         uses: actions/setup-node@v3
         with:
@@ -50,30 +50,19 @@ jobs:
         uses: actions/setup-python@v4
         with:
           python-version: '3.7'
+          cache: pip
       - name: Install python3-venv
         run: sudo apt install -y python3-venv
-      - name: Locate Caches
-        id: cache-locations
-        run: |-
-          echo "::group::Upgrade pip"
-          # Need to have PIP >= 20.1 for "pip cache dir" to work
-          python3 -m pip install --upgrade pip
-          echo "::endgroup"
-
-          echo "::set-output name=pip-cache::$(python3 -m pip cache dir)"
       - name: Cache
         uses: actions/cache@v3
         with:
           path: |-
-            ${{ steps.cache-locations.outputs.pip-cache }}
             ~/.m2/repository
             !~/.m2/repository/software/amazon/jsii/
             ~/.nuget/packages
             !~/.nuget/packages/amazon.jsii.*
-          key: ${{ runner.os }}-node@[email protected]${{ hashFiles('**/yarn.lock', '**/Directory.Build.targets') }}
+          key: ${{ runner.os }}-${{ hashFiles('**/Directory.Build.targets') }}
           restore-keys: |-
-            ${{ runner.os }}-node@[email protected]
-            ${{ runner.os }}-node@14-
             ${{ runner.os }}-
       # Prepare dependencies and build
       - name: Install Dependencies
@@ -133,8 +122,8 @@ jobs:
       - name: Set up Java 8
         uses: actions/setup-java@v3
         with:
-          java-version: '8'
           distribution: 'zulu'
+          java-version: '8'
       - name: Set up Node 14
         uses: actions/setup-node@v3
         with:
@@ -144,30 +133,19 @@ jobs:
         uses: actions/setup-python@v4
         with:
           python-version: '3.7'
+          cache: pip
       - name: Install python3-venv
         run: sudo apt install -y python3-venv
-      - name: Locate Caches
-        id: cache-locations
-        run: |-
-          echo "::group::Upgrade pip"
-          # Need to have PIP >= 20.1 for "pip cache dir" to work
-          python3 -m pip install --upgrade pip
-          echo "::endgroup"
-
-          echo "::set-output name=pip-cache::$(python3 -m pip cache dir)"
       - name: Cache
         uses: actions/cache@v3
         with:
           path: |-
-            ${{ steps.cache-locations.outputs.pip-cache }}
             ~/.m2/repository
             !~/.m2/repository/software/amazon/jsii/
             ~/.nuget/packages
             !~/.nuget/packages/amazon.jsii.*
-          key: ${{ runner.os }}-node@[email protected]${{ hashFiles('**/yarn.lock', '**/Directory.Build.targets') }}
+          key: ${{ runner.os }}-${{ hashFiles('**/Directory.Build.targets') }}
           restore-keys: |-
-            ${{ runner.os }}-node@[email protected]
-            ${{ runner.os }}-node@14-
             ${{ runner.os }}-
       # Prepare dependencies and build
       - name: Install Dependencies
@@ -319,8 +297,8 @@ jobs:
       - name: Set up Java ${{ matrix.java }}
         uses: actions/setup-java@v3
         with:
-          java-version: ${{ matrix.java }}
           distribution: 'zulu'
+          java-version: ${{ matrix.java }}
       - name: Set up Node ${{ matrix.node }}
         uses: actions/setup-node@v3
         with:
@@ -330,32 +308,21 @@ jobs:
         uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python }}
+          cache: pip
       - name: 'Linux: Install python3-venv'
         if: runner.os == 'Linux'
         run: sudo apt install -y python3-venv
-      - name: Locate Caches
-        id: cache-locations
-        run: |-
-          echo "::group::Upgrade pip"
-          # Need to have PIP >= 20.1 for "pip cache dir" to work
-          python3 -m pip install --upgrade pip
-          echo "::endgroup"
-
-          echo "::set-output name=pip-cache::$(python3 -m pip cache dir)"
       - name: Cache
         uses: actions/cache@v3
         with:
           path: |-
-            ${{ steps.cache-locations.outputs.pip-cache }}
             ~/.m2/repository
             !~/.m2/repository/software/amazon/jsii/
             ~/.nuget/packages
             !~/.nuget/packages/amazon.jsii.*
           # Not including .NET / Java in the cache keys, those artifacts are SDK-version-independent
-          key: ${{ runner.os }}-node@${{ matrix.node }}-python@${{ matrix.python }}-${{ hashFiles('**/yarn.lock', '**/Directory.Build.targets') }}
+          key: ${{ runner.os }}-${{ hashFiles('**/Directory.Build.targets') }}
           restore-keys: |-
-            ${{ runner.os }}-node@${{ matrix.node }}-python@${{ matrix.python }}-
-            ${{ runner.os }}-node@${{ matrix.node }}-
             ${{ runner.os }}-
       # Run the tests
       - name: Install Dependencies
@@ -426,3 +393,55 @@ jobs:
           output-file-path: ${{ runner.temp }}/bench-output.json
           github-token: ${{ secrets.PROJEN_GITHUB_TOKEN }}
           auto-push: true
+
+  pacmak-integration-test:
+    name: Integration test (jsii-pacmak)
+    runs-on: ubuntu-latest
+    needs: create-release-package
+    steps:
+      # Check out the code
+      - name: Download Artifact
+        uses: actions/download-artifact@v3
+        with:
+          name: release-package
+          path: ${{ runner.temp }}/release-package
+      # Set up all of our standard runtimes
+      - name: Set up .NET 6
+        uses: actions/setup-dotnet@v2
+        with:
+          dotnet-version: '6.0.x'
+      - name: Set up Go 1.18
+        uses: actions/setup-go@v3
+        with:
+          go-version: '1.18'
+      - name: Set up Java 8
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: '8'
+      - name: Set up Node 14
+        uses: actions/setup-node@v3
+        with:
+          node-version: '14'
+      - name: Set up Python 3.7
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.7'
+      - name: Install python3-venv
+        run: sudo apt install -y python3-venv
+      # Show time!
+      - name: Prepare Work Tree
+        run: |-
+          npm install --no-save aws-cdk-lib@2 constructs@10                     \
+                                ${{ runner.temp }}/release-package/js/*.tgz     \
+                                ${{ runner.temp }}/release-package/private/*.tgz
+      - name: Run jsii-pacmak on aws-cdk-lib
+        run: |-
+          ./node_modules/.bin/jsii-pacmak ./node_modules/aws-cdk-lib
+      # Upload artifact (we'll tar it up to save time)
+      - name: 'Upload Artifact: integtest_aws-cdk-lib'
+        uses: actions/upload-artifact@v3
+        with:
+          name: integtest_aws-cdk-lib
+          path: ./node_modules/aws-cdk-lib/dist/
+

packages/jsii-pacmak/lib/targets/java.ts

@@ -1,4 +1,5 @@
 import * as spec from '@jsii/spec';
+import * as assert from 'assert';
 import * as clone from 'clone';
 import { toSnakeCase } from 'codemaker/lib/case-utils';
 import { createHash } from 'crypto';
@@ -1472,9 +1473,20 @@ class JavaGenerator extends Generator {
           // so we should not emit these checks for primitive-only unions.
           // Also, Java does not allow us to perform these checks if the types
           // have no overlap (eg if a String instanceof Number).
-          if (type.includes('java.lang.Object')) {
+          if (
+            type.includes('java.lang.Object') &&
+            (!spec.isPrimitiveTypeReference(prop.type) ||
+              prop.type.primitive === spec.PrimitiveType.Any)
+          ) {
             this.emitUnionParameterValdation([
-              { name: 'value', type: prop.type },
+              {
+                name: 'value',
+                type: this.filterType(
+                  prop.type,
+                  { covariant: prop.static, optional: prop.optional },
+                  type,
+                ),
+              },
             ]);
           }
           if (prop.static) {
@@ -1493,6 +1505,40 @@ class JavaGenerator extends Generator {
     }
   }
 
+  /**
+   * Filters types from a union to select only those that correspond to the
+   * specified javaType.
+   *
+   * @param ref the type to be filtered.
+   * @param javaType the java type that is expected.
+   * @param covariant whether collections should use the covariant form.
+   * @param optional whether the type at an optional location or not
+   *
+   * @returns a type reference that matches the provided javaType.
+   */
+  private filterType(
+    ref: spec.TypeReference,
+    { covariant, optional }: { covariant?: boolean; optional?: boolean },
+    javaType: string,
+  ): spec.TypeReference {
+    if (!spec.isUnionTypeReference(ref)) {
+      // No filterning needed -- this isn't a type union!
+      return ref;
+    }
+    const types = ref.union.types.filter(
+      (t) =>
+        this.toDecoratedJavaType({ optional, type: t }, { covariant }) ===
+        javaType,
+    );
+    assert(
+      types.length > 0,
+      `No type found in ${spec.describeTypeReference(
+        ref,
+      )} has Java type ${javaType}`,
+    );
+    return { union: { types } };
+  }
+
   private emitMethod(
     cls: spec.Type,
     method: spec.Method,
@@ -1715,69 +1761,87 @@ class JavaGenerator extends Generator {
       type: spec.UnionTypeReference,
       parameterName: string,
     ) {
-      this.code.indent('if (');
       let emitAnd = false;
-      const nestedCollectionUnionTypes = [];
+      const nestedCollectionUnionTypes = new Map<string, spec.TypeReference>();
       const typeRefs = type.union.types;
+      if (typeRefs.length > 1) {
+        this.code.indent('if (');
+      }
+      const checked = new Set<string>();
       for (const typeRef of typeRefs) {
         const prefix = emitAnd ? '&&' : '';
-        const javaType = this.toJavaTypeNoGenerics(typeRef);
-        if (javaType !== this.toJavaType(typeRef)) {
-          nestedCollectionUnionTypes.push(typeRef);
+        const javaRawType = this.toJavaTypeNoGenerics(typeRef);
+        if (checked.has(javaRawType)) {
+          continue;
+        } else {
+          checked.add(javaRawType);
+        }
+        const javaType = this.toJavaType(typeRef);
+        if (javaRawType !== javaType) {
+          nestedCollectionUnionTypes.set(javaType, typeRef);
+        }
+        const test = `${value} instanceof ${javaRawType}`;
+        if (typeRefs.length > 1) {
+          this.code.line(`${prefix} !(${test})`);
         }
-        const test = `${value} instanceof ${javaType}`;
-        this.code.line(`${prefix} !(${test})`);
         emitAnd = true;
       }
-      // Only anonymous objects at runtime can be `JsiiObject`s.
-      this.code.line(
-        `&& !(${value}.getClass().equals(software.amazon.jsii.JsiiObject.class))`,
-      );
-
-      this.code.unindent(')');
-      this.code.openBlock('');
-
-      const placeholders = typeRefs
-        .map((typeRef) => {
-          return `${this.toJavaType(typeRef)}`;
-        })
-        .join(', ');
-
-      this.code.indent(`throw new IllegalArgumentException(`);
-      this.code.indent(`new java.lang.StringBuilder("Expected ")`);
-      this.code.line(descr);
-      this.code.line(`.append(" to be one of: ${placeholders}; received ")`);
-      this.code.line(`.append(${value}.getClass()).toString());`);
-      this.code.unindent(false);
-      this.code.unindent(false);
-      this.code.closeBlock();
-
-      for (const typeRef of nestedCollectionUnionTypes) {
-        this.code.openBlock(
-          `if (${value} instanceof ${this.toJavaTypeNoGenerics(typeRef)})`,
-        );
-        const varName = `__cast_${createHash('sha256')
-          .update(value)
-          .digest('hex')
-          .slice(0, 6)}`;
-        const javaTypeFull = this.toJavaType(typeRef);
-        this.code.line(`@SuppressWarnings("unchecked")`);
+      if (
+        typeRefs.length > 1 &&
+        typeRefs.some(
+          (t) =>
+            spec.isNamedTypeReference(t) &&
+            spec.isInterfaceType(this.findType(t.fqn)),
+        )
+      ) {
+        // Only anonymous objects at runtime can be `JsiiObject`s.
         this.code.line(
-          `final ${javaTypeFull} ${varName} = (${javaTypeFull})${value};`,
-        );
-        validate.call(this, varName, descr, typeRef, parameterName);
-        validate.call(
-          this,
-          // we must cast Collections to access their methods
-          // if they are nested in a union type,
-          // since that union will be rendered as an Object.
-          `((${this.toJavaType(typeRef)})(${varName}))`,
-          descr,
-          typeRef,
-          parameterName,
+          `&& !(${value}.getClass().equals(software.amazon.jsii.JsiiObject.class))`,
         );
+      }
+
+      if (typeRefs.length > 1) {
+        this.code.unindent(false);
+        this.code.openBlock(')');
+
+        const placeholders = typeRefs
+          .map((typeRef) => {
+            return `${this.toJavaType(typeRef)}`;
+          })
+          .join(', ');
+
+        this.code.indent(`throw new IllegalArgumentException(`);
+        this.code.indent(`new java.lang.StringBuilder("Expected ")`);
+        this.code.line(descr);
+        this.code.line(`.append(" to be one of: ${placeholders}; received ")`);
+        this.code.line(`.append(${value}.getClass()).toString());`);
+        this.code.unindent(false);
+        this.code.unindent(false);
         this.code.closeBlock();
       }
+
+      for (const [javaType, typeRef] of nestedCollectionUnionTypes) {
+        const varName =
+          typeRefs.length > 1
+            ? `__cast_${createHash('sha256')
+                .update(value)
+                .digest('hex')
+                .slice(0, 6)}`
+            : value;
+        if (typeRefs.length > 1) {
+          this.code.openBlock(
+            `if (${value} instanceof ${this.toJavaTypeNoGenerics(typeRef)})`,
+          );
+          this.code.line(`@SuppressWarnings("unchecked")`);
+          this.code.line(
+            `final ${javaType} ${varName} = (${javaType})${value};`,
+          );
+        }
+        validate.call(this, varName, descr, typeRef, parameterName);
+        if (typeRefs.length > 1) {
+          this.code.closeBlock();
+        }
+      }
     }
   }