Make genrule.exec_tools only exist in Bazel.

This is a step towards removing it entirely, see #19132.

Next step is to add an actual incompatible flag if possible.

RELNOTES: The `genrule` attribute `exec_tools` will be removed in a future Bazel release. Please follow directions at #19132 to migrate away from it.
PiperOrigin-RevId: 552469827
Change-Id: Ica480e1113a1b8aeae31ad0713c41660416248b6

Author: katre

src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BUILD

@@ -20,5 +20,6 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/analysis:rule_definition_environment",
         "//src/main/java/com/google/devtools/build/lib/packages",
         "//src/main/java/com/google/devtools/build/lib/rules/genrule",
+        "//src/main/java/com/google/devtools/build/lib/util:filetype",
     ],
 )

src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRule.java

@@ -14,6 +14,7 @@
 
 package com.google.devtools.build.lib.bazel.rules.genrule;
 
+import com.google.devtools.build.lib.analysis.CommandHelper;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.packages.Type;
 import com.google.devtools.build.lib.rules.genrule.GenRuleBase;
@@ -30,4 +31,15 @@ protected boolean isStampingEnabled(RuleContext ruleContext) {
     }
     return ruleContext.attributes().get("stamp", Type.BOOLEAN);
   }
+
+  // TODO(https://github.com/bazelbuild/bazel/issues/19132): Remove this override once downstream
+  // projects are migrated.
+  @Override
+  protected CommandHelper.Builder commandHelperBuilder(RuleContext ruleContext) {
+    return CommandHelper.builder(ruleContext)
+        .addToolDependencies("tools")
+        // TODO(https://github.com/bazelbuild/bazel/issues/19132): Add an actual incompatible flag.
+        .addToolDependencies("exec_tools")
+        .addToolDependencies("toolchains");
+  }
 }

src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java

@@ -15,13 +15,15 @@
 
 import static com.google.devtools.build.lib.packages.Attribute.attr;
 import static com.google.devtools.build.lib.packages.BuildType.LABEL;
+import static com.google.devtools.build.lib.packages.BuildType.LABEL_LIST;
 import static com.google.devtools.build.lib.packages.Type.BOOLEAN;
 
 import com.google.devtools.build.lib.analysis.RuleDefinition;
 import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment;
 import com.google.devtools.build.lib.analysis.config.ExecutionTransitionFactory;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.rules.genrule.GenRuleBaseRule;
+import com.google.devtools.build.lib.util.FileTypeSet;
 
 /**
  * Rule definition for genrule for Bazel.
@@ -44,6 +46,23 @@ public RuleClass build(RuleClass.Builder builder, RuleDefinitionEnvironment env)
                 .cfg(ExecutionTransitionFactory.createFactory())
                 .value(env.getToolsLabel(GENRULE_SETUP_LABEL)))
 
+        // TODO(https://github.com/bazelbuild/bazel/issues/19132): Remove this once downstream
+        // projects are migrated.
+        /* <!-- #BLAZE_RULE(genrule).ATTRIBUTE(exec_tools) -->
+        <b>Deprecated. Use <a href="#genrule.tools"><code>tools</code></a> instead.</b>
+
+        <p>
+          There was a period of time when <code>exec_tools</code> and <code>tools</code> behaved
+          differently, but they are now equivalent and the Blaze team will be migrating all uses of
+          <code>exec_tools</code> to <code>tools</code>.
+        </p>
+        <!-- #END_BLAZE_RULE.ATTRIBUTE --> */
+        .add(
+            attr("exec_tools", LABEL_LIST)
+                .cfg(ExecutionTransitionFactory.createFactory())
+                .allowedFileTypes(FileTypeSet.ANY_FILE)
+                .dontCheckConstraints())
+
         // TODO(bazel-team): stamping doesn't seem to work. Fix it or remove attribute.
         .add(attr("stamp", BOOLEAN).value(false))
         .build();

src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBase.java

@@ -289,7 +289,6 @@ public String toString() {
   protected CommandHelper.Builder commandHelperBuilder(RuleContext ruleContext) {
     return CommandHelper.builder(ruleContext)
         .addToolDependencies("tools")
-        .addToolDependencies("exec_tools")
         .addToolDependencies("toolchains");
   }
 

src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBaseRule.java

@@ -85,21 +85,6 @@ public RuleClass build(
                 .cfg(ExecutionTransitionFactory.createFactory())
                 .allowedFileTypes(FileTypeSet.ANY_FILE))
 
-        /* <!-- #BLAZE_RULE(genrule).ATTRIBUTE(exec_tools) -->
-        <b>Deprecated. Use <a href="#genrule.tools"><code>tools</code></a> instead.</b>
-
-        <p>
-          There was a period of time when <code>exec_tools</code> and <code>tools</code> behaved
-          differently, but they are now equivalent and the Blaze team will be migrating all uses of
-          <code>exec_tools</code> to <code>tools</code>.
-        </p>
-        <!-- #END_BLAZE_RULE.ATTRIBUTE --> */
-        .add(
-            attr("exec_tools", LABEL_LIST)
-                .cfg(ExecutionTransitionFactory.createFactory())
-                .allowedFileTypes(FileTypeSet.ANY_FILE)
-                .dontCheckConstraints())
-
         /* <!-- #BLAZE_RULE(genrule).ATTRIBUTE(outs) -->
         A list of files generated by this rule.
         <p>