[ggj][codegen] fix: init remaining resname tokenVars to null (#329)

* feat: add protobuf comment parser util

* fix: add basic proto build rules

* feat: add header comments to ServiceClient

* fix: build protoc at test time

* fix!: wrap protobuf location and process comments

* feat: add comment parsing to methods and fields

* fix: test

* feat: add protobuf comments to ServiceClient

* fix: solidify codegen method order with TypeNode/MethodArg and Comparable

* fix: clean up tests

* fix: ServiceClient member variables and method calls

* fix: ServiceStubSettings builder type

* fix: ServiceSettings Builder construction

* fix: ServiceStub callable types

* feat: java_gapic_library rule impl

* fix: remove debugging comments

* feat: add gradle assembly Bazel rules

* feat: add java_gapic_test Bazel rule

* fix: use Java packages for resname codegen

* fix: build resnames separately and extract into proto/ dir

* fix: remove debug printf

* feat: add ServiceClient.MethodPagedResponse inner class

* feat: add ServiceClient.MethodPage inner class

* feat: add ServiceClient.MethodFixedSizeCollection innser class

* fix: clean up resname codegen, lower_snake varnames

* fix: init remaining resname tokenVars to null

src/main/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposer.java

@@ -312,6 +312,18 @@ private static List<MethodDefinition> createConstructorMethods(
                 .setValueExpr(checkNotNullExpr)
                 .build());
       }
+      // Initialize the rest to null.
+      ValueExpr nullExpr = ValueExpr.withValue(NullObjectValue.create());
+      for (String token : getTokenSet(tokenHierarchies)) {
+        if (tokens.contains(token)) {
+          continue;
+        }
+        bodyExprs.add(
+            AssignmentExpr.builder()
+                .setVariableExpr(patternTokenVarExprs.get(token))
+                .setValueExpr(nullExpr)
+                .build());
+      }
 
       if (hasVariants) {
         AssignmentExpr pathTemplateAssignExpr =

src/test/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposerTest.java

@@ -245,24 +245,32 @@ public void generateResourceNameClass_testingSessionOnePattern() {
           + "  private FoobarName(Builder builder) {\n"
           + "    project = Preconditions.checkNotNull(builder.getProject());\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    variant = null;\n"
+          + "    barFoo = null;\n"
           + "    pathTemplate = PROJECT_FOOBAR;\n"
           + "  }\n"
           + "\n"
           + "  private FoobarName(ProjectVariantFoobarBuilder builder) {\n"
           + "    project = Preconditions.checkNotNull(builder.getProject());\n"
           + "    variant = Preconditions.checkNotNull(builder.getVariant());\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    barFoo = null;\n"
           + "    pathTemplate = PROJECT_VARIANT_FOOBAR;\n"
           + "  }\n"
           + "\n"
           + "  private FoobarName(FoobarBuilder builder) {\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    project = null;\n"
+          + "    variant = null;\n"
+          + "    barFoo = null;\n"
           + "    pathTemplate = FOOBAR;\n"
           + "  }\n"
           + "\n"
           + "  private FoobarName(BarFooFoobarBuilder builder) {\n"
           + "    barFoo = Preconditions.checkNotNull(builder.getBarFoo());\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    project = null;\n"
+          + "    variant = null;\n"
           + "    pathTemplate = BAR_FOO_FOOBAR;\n"
           + "  }\n"
           + "\n"