Accept labels of aliases in config_setting.

Previously, if a config_setting referenced a Starlark setting through an alias, it was always evaluated as if the setting had its default value. Now, it is evaluated correctly. This is done by looking up the value of the build setting in the configuration based on its own label as specified in BuildSettingProvider. Fixes #13463 . RELNOTES: None. PiperOrigin-RevId: 585658985 Change-Id: Id534cd95282355f1143302bf703145bb53708a41
bazelbuild · Nov 27, 2023 · d44c3f9 · d44c3f9
1 parent 67021ff
commit d44c3f9
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Showing 3 changed files with 58 additions and 4 deletions.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/config/ConfigSetting.java b/src/main/java/com/google/devtools/build/lib/rules/config/ConfigSetting.java
@@ -497,10 +497,14 @@ static UserDefinedFlagMatch fromAttributeValueAndPrerequisites(
         } else if (target.satisfies(BuildSettingProvider.REQUIRE_BUILD_SETTING_PROVIDER)) {
           // build setting
           BuildSettingProvider provider = target.getProvider(BuildSettingProvider.class);
-          Object configurationValue =
-              optionDetails.getOptionValue(specifiedLabel) != null
-                  ? optionDetails.getOptionValue(specifiedLabel)
-                  : provider.getDefaultValue();
+
+          Object configurationValue;
+          if (optionDetails.getOptionValue(provider.getLabel()) != null) {
+            configurationValue = optionDetails.getOptionValue(provider.getLabel());
+          } else {
+            configurationValue = provider.getDefaultValue();
+          }
+
           Object convertedSpecifiedValue;
           try {
             // We don't need to supply a base package or repo mapping for the conversion here,

diff --git a/src/test/java/com/google/devtools/build/lib/rules/LabelBuildSettingTest.java b/src/test/java/com/google/devtools/build/lib/rules/LabelBuildSettingTest.java
@@ -116,6 +116,35 @@ public void testLabelFlag_set() throws Exception {
     assertThat(b.get("value")).isEqualTo("command_line_value");
   }
 
+  @Test
+  public void withSelectThroughAlias() throws Exception {
+    writeRulesBzl("flag");
+    scratch.file(
+        "test/BUILD",
+        "load('//test:rules.bzl', 'my_rule', 'simple_rule')",
+        "simple_rule(name = 'default', value = 'default_value')",
+        "simple_rule(name = 'command_line', value = 'command_line_value')",
+        "label_flag(name = 'my_label_flag', build_setting_default = ':default')",
+        "alias(name = 'my_label_flag_alias', actual = ':my_label_flag')",
+        "config_setting(",
+        "    name = 'is_default_label',",
+        "    flag_values = {':my_label_flag_alias': '//test:default'}",
+        ")",
+        "simple_rule(name = 'selector', value = select({':is_default_label': 'valid'}))");
+
+    useConfiguration();
+    getConfiguredTarget("//test:selector");
+    assertNoEvents();
+
+    reporter.removeHandler(failFastHandler);
+    useConfiguration(
+        ImmutableMap.of(
+            "//test:my_label_flag", Label.parseCanonicalUnchecked("//test:command_line")));
+    getConfiguredTarget("//test:selector");
+    assertContainsEvent(
+        "configurable attribute \"value\" in //test:selector doesn't match this configuration");
+  }
+
   @Test
   public void withSelect() throws Exception {
     writeRulesBzl("flag");

diff --git a/src/test/java/com/google/devtools/build/lib/rules/config/ConfigSettingTest.java b/src/test/java/com/google/devtools/build/lib/rules/config/ConfigSettingTest.java
@@ -2177,6 +2177,27 @@ public void ruleLicensesUsed() throws Exception {
     assertThat(getLicenses("//test:match")).containsExactly(LicenseType.NONE);
   }
 
+  @Test
+  public void aliasedStarlarkFlag() throws Exception {
+    scratch.file(
+        "test/flagdef.bzl",
+        "def _impl(ctx):",
+        "    return []",
+        "my_flag = rule(",
+        "    implementation = _impl,",
+        "    build_setting = config.string(flag = True))");
+
+    scratch.file(
+        "test/BUILD",
+        "load('//test:flagdef.bzl', 'my_flag')",
+        "my_flag(name = 'flag', build_setting_default = 'default')",
+        "alias(name = 'alias', actual = ':flag')",
+        "config_setting(name = 'alias_setting', flag_values = {':alias': 'specified'})");
+
+    useConfiguration(ImmutableMap.of("//test:flag", "specified"));
+    assertThat(getConfigMatchingProviderResultAsBoolean("//test:alias_setting")).isTrue();
+  }
+
   @Test
   public void simpleStarlarkFlag() throws Exception {
     scratch.file(