Add a DEVELOPER_DIR make variable to genrules to propagate the apple xcode environment variable DEVELOPER_DIR to commands.

If $(DEVELOPER_DIR) is included in the genrule command, we bootstrap the XCODE_VERSION_OVERRIDE environment variable to the command.
The contract with the actual action executor is, if XCODE_VERSION_OVERRIDE is present in the environment, to additionally bootstrap the DEVELOPER_DIR absolute path to the command.

--
MOS_MIGRATED_REVID=112605616

3 files changed, 26 insertions, 4 deletions

diff --git a/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm b/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm
index 684f998b8f..8433d4903e 100644
--- a/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm
+++ b/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm
@@ -126,6 +126,10 @@ in your genrule's cmd attribute.
     the tool is to use <code>$(location <i>toolname</i>)</code>,
     where <i>toolname</i> must be listed in the <code>tools</code>
     attribute for the genrule.</li>
+  <li><code>DEVELOPER_DIR</code>:
+    The base developer directory as defined on Apple architectures, most commonly
+    used in invoking Apple tools such as <code>xcrun</code>.
+    Supported only on Apple execution hosts.</li>
   <li><code>GENDIR</code>: The base of the generated code
     tree for the target architecture.</li>
   <li><code>JAVABASE</code>:
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java
index 593d32aed2..e153e13e5e 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java
@@ -31,6 +31,8 @@ import com.google.devtools.build.lib.packages.AttributeMap;
 import com.google.devtools.build.lib.packages.BuildType;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.packages.RuleClass.Builder;
+import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
+import com.google.devtools.build.lib.rules.apple.AppleToolchain.RequiresXcodeConfigRule;
 
 /**
  * Rule definition for the genrule rule.
@@ -47,6 +49,7 @@ public final class BazelGenRuleRule implements RuleDefinition {
     <code>srcs</code> attribute.
     <!-- #END_BLAZE_RULE.NAME --> */
     return builder
+        .requiresConfigurationFragments(AppleConfiguration.class)
         .setOutputToGenfiles()
         /* <!-- #BLAZE_RULE(genrule).ATTRIBUTE(srcs) -->
         A list of inputs for this rule, such as source files to process.
@@ -215,7 +218,7 @@ public final class BazelGenRuleRule implements RuleDefinition {
   public Metadata getMetadata() {
     return RuleDefinition.Metadata.builder()
         .name("genrule")
-        .ancestors(BaseRuleClasses.RuleBase.class)
+        .ancestors(BaseRuleClasses.RuleBase.class, RequiresXcodeConfigRule.class)
         .factoryClass(GenRule.class)
         .build();
   }
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java
index d9c855a32a..63fa6457de 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java
@@ -39,17 +39,23 @@ import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.packages.TargetUtils;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
+import com.google.devtools.build.lib.rules.apple.AppleToolchain;
+import com.google.devtools.build.lib.rules.apple.XcodeConfigProvider;
 import com.google.devtools.build.lib.syntax.Type;
 import com.google.devtools.build.lib.vfs.PathFragment;
 
 import java.util.List;
 import java.util.Map;
+import java.util.regex.Pattern;
 
 /**
  * An implementation of genrule.
  */
 public class GenRule implements RuleConfiguredTargetFactory {
 
+  private static final Pattern DEVELOPER_DIR_MAKE_VARIABLE =
+      Pattern.compile("\\$\\((DEVELOPER_DIR)\\)");
+
   private Artifact getExecutable(RuleContext ruleContext, NestedSet<Artifact> filesToBuild) {
     if (Iterables.size(filesToBuild) == 1) {
       Artifact out = Iterables.getOnlyElement(filesToBuild);
@@ -99,6 +105,15 @@ public class GenRule implements RuleConfiguredTargetFactory {
     String command = String.format("source %s; %s",
         ruleContext.getPrerequisiteArtifact("$genrule_setup", Mode.HOST).getExecPath(),
         baseCommand);
+    
+    ImmutableMap.Builder<String, String> envBuilder = ImmutableMap.<String, String>builder()
+        .putAll(ruleContext.getConfiguration().getLocalShellEnvironment());
+    
+    if (DEVELOPER_DIR_MAKE_VARIABLE.matcher(command).find()) {
+      XcodeConfigProvider xcodeConfigProvider =
+          ruleContext.getPrerequisite(":xcode_config", Mode.HOST, XcodeConfigProvider.class);
+      envBuilder.putAll(AppleToolchain.appleHostSystemEnv(xcodeConfigProvider));
+    }
 
     command = resolveCommand(ruleContext, command, resolvedSrcs, filesToBuild);
 
@@ -107,8 +122,6 @@ public class GenRule implements RuleConfiguredTargetFactory {
       message = "Executing genrule";
     }
 
-    ImmutableMap<String, String> env = ruleContext.getConfiguration().getLocalShellEnvironment();
-
     Map<String, String> executionInfo = Maps.newLinkedHashMap();
     executionInfo.putAll(TargetUtils.getExecutionInfo(ruleContext.getRule()));
 
@@ -136,7 +149,7 @@ public class GenRule implements RuleConfiguredTargetFactory {
             inputs.build(),
             filesToBuild,
             argv,
-            env,
+            envBuilder.build(),
             ImmutableMap.copyOf(executionInfo),
             commandHelper.getRemoteRunfileManifestMap(),
             message + ' ' + ruleContext.getLabel()));
@@ -198,6 +211,8 @@ public class GenRule implements RuleConfiguredTargetFactory {
                 PathFragment relPath = ruleContext.getRule().getLabel().getPackageFragment();
                 return dir.getRelative(relPath).getPathString();
               }
+            } else if (DEVELOPER_DIR_MAKE_VARIABLE.matcher("$(" + name + ")").find()) {
+              return "$${DEVELOPER_DIR}";
             } else {
               return super.lookupMakeVariable(name);
             }