Support coverage in experimental_ios_test.

Coverage depends on quite a few moving parts, several of which were changed for this test:

- BuildConfiguration.getCoverageLabels() used to include gcov support, this is now replaced by the dedicated getGcovLabels() and a separate implicit attribute on TestBaseRule. This new attribute is then overridden in ExperimentalIosTest to use an xcode-compatible gcov.
- Objc's TestSupport now correctly registers instrumented files and sets the necessary runfiles for collecting coverage.
- ios_test's template exports gcda files for coverage computation after the test's execution.

--
MOS_MIGRATED_REVID=99374435

1 files changed, 19 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalIosTestRule.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalIosTestRule.java
index 2a866b720c..7bf6ec2993 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalIosTestRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalIosTestRule.java
@@ -14,20 +14,28 @@
 
 package com.google.devtools.build.lib.rules.objc;
 
+import static com.google.devtools.build.lib.packages.Attribute.ConfigurationTransition.HOST;
 import static com.google.devtools.build.lib.packages.Attribute.attr;
 import static com.google.devtools.build.lib.packages.Type.LABEL;
 import static com.google.devtools.build.lib.packages.Type.LABEL_LIST;
 import static com.google.devtools.build.lib.packages.Type.STRING_LIST;
 
+import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.Constants;
 import com.google.devtools.build.lib.analysis.BaseRuleClasses;
 import com.google.devtools.build.lib.analysis.RuleDefinition;
 import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment;
+import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.packages.Attribute.LateBoundLabelList;
 import com.google.devtools.build.lib.packages.ImplicitOutputsFunction;
+import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.packages.RuleClass.Builder.RuleClassType;
+import com.google.devtools.build.lib.syntax.Label;
 import com.google.devtools.build.lib.util.FileType;
 
+import java.util.List;
+
 /**
  * Rule definition for {@code experimental_ios_test} rule in Bazel.
  *
@@ -78,6 +86,17 @@ public final class ExperimentalIosTestRule implements RuleDefinition {
         .add(attr("$test_template", LABEL)
             .value(env.getLabel("//tools/objc:ios_test.sh.bazel_template")))
         .add(attr("$test_runner", LABEL).value(env.getLabel("//tools/objc:testrunner")))
+        .override(attr(":gcov", LABEL_LIST).cfg(HOST)
+            .value(new LateBoundLabelList<BuildConfiguration>() {
+              @Override
+              public List<Label> getDefault(Rule rule, BuildConfiguration configuration) {
+                if (!configuration.isCodeCoverageEnabled()) {
+                  return ImmutableList.of();
+                }
+                return ImmutableList.of(
+                    configuration.getFragment(ObjcConfiguration.class).getGcovLabel());
+              }
+            }))
         .build();
   }