Let select() "unset" values via: select({"//some:condition: None }).

This not only uses the default value when applicable, but also causes
ConfiguredAttributeMapper.isAttributeValueExplicitlySpecified to
return false.

Note the default value can come from two places: from the rule
definition if specified, otherwise from the type default.

RELNOTES[NEW]: select({"//some:condition: None }) is now possible (this "unsets" the attribute).

--
MOS_MIGRATED_REVID=121029815

2 files changed, 47 insertions, 3 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/select/AbstractAttributeMapperTest.java b/src/test/java/com/google/devtools/build/lib/analysis/select/AbstractAttributeMapperTest.java
index beb15a8f97..4ecd5ed560 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/select/AbstractAttributeMapperTest.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/select/AbstractAttributeMapperTest.java
@@ -137,9 +137,15 @@ public class AbstractAttributeMapperTest extends FoundationTestCase {
 
   protected static class VisitationRecorder implements AttributeMap.AcceptsLabelAttribute {
     public List<String> labelsVisited = Lists.newArrayList();
+    private final String attrName;
+
+    public VisitationRecorder(String attrName) {
+      this.attrName = attrName;
+    }
+
     @Override
     public void acceptLabelAttribute(Label label, Attribute attribute) {
-      if (attribute.getName().equals("srcs")) {
+      if (attribute.getName().equals(attrName)) {
         labelsVisited.add(label.toString());
       }
     }
@@ -147,7 +153,7 @@ public class AbstractAttributeMapperTest extends FoundationTestCase {
 
   @Test
   public void testVisitation() throws Exception {
-    VisitationRecorder recorder = new VisitationRecorder();
+    VisitationRecorder recorder = new VisitationRecorder("srcs");
     mapper.visitLabels(recorder);
     assertThat(recorder.labelsVisited)
         .containsExactlyElementsIn(ImmutableList.of("//x:a", "//x:b", "//x:c"));
diff --git a/src/test/java/com/google/devtools/build/lib/analysis/select/AggregatingAttributeMapperTest.java b/src/test/java/com/google/devtools/build/lib/analysis/select/AggregatingAttributeMapperTest.java
index 4aafb58752..e9f4305d29 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/select/AggregatingAttributeMapperTest.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/select/AggregatingAttributeMapperTest.java
@@ -16,6 +16,7 @@ package com.google.devtools.build.lib.analysis.select;
 import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertNull;
 
+import com.google.common.base.Verify;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.devtools.build.lib.cmdline.Label;
@@ -43,6 +44,11 @@ public class AggregatingAttributeMapperTest extends AbstractAttributeMapperTest
     mapper = AggregatingAttributeMapper.of(rule);
   }
 
+  private static Label getDefaultMallocLabel(Rule rule) {
+    return Verify.verifyNotNull(
+        (Label) rule.getRuleClassObject().getAttributeByName("malloc").getDefaultValueForTesting());
+  }
+
   /**
    * Tests that {@link AggregatingAttributeMapper#visitAttribute} returns an
    * attribute's sole value when declared directly (i.e. not as a configurable dict).
@@ -130,7 +136,7 @@ public class AggregatingAttributeMapperTest extends AbstractAttributeMapperTest
         "              '" + BuildType.Selector.DEFAULT_CONDITION_KEY + "': ['default.sh'],",
         "          }))");
 
-    VisitationRecorder recorder = new VisitationRecorder();
+    VisitationRecorder recorder = new VisitationRecorder("srcs");
     AggregatingAttributeMapper.of(rule).visitLabels(recorder);
     assertThat(recorder.labelsVisited)
         .containsExactlyElementsIn(
@@ -139,6 +145,23 @@ public class AggregatingAttributeMapperTest extends AbstractAttributeMapperTest
   }
 
   @Test
+  public void testVisitationWithDefaultValues() throws Exception {
+    Rule rule = createRule("a", "myrule",
+        "cc_binary(name = 'myrule',",
+        "    srcs = [],",
+        "    malloc = select({",
+        "        '//conditions:a': None,",
+        "    }))");
+
+    VisitationRecorder recorder = new VisitationRecorder("malloc");
+    AggregatingAttributeMapper.of(rule).visitLabels(recorder);
+    assertThat(recorder.labelsVisited)
+        .containsExactlyElementsIn(
+            ImmutableList.of("//conditions:a", getDefaultMallocLabel(rule).toString()));
+  }
+
+
+  @Test
   public void testGetReachableLabels() throws Exception {
     Rule rule = createRule("x", "main",
         "cc_binary(",
@@ -170,6 +193,21 @@ public class AggregatingAttributeMapperTest extends AbstractAttributeMapperTest
   }
 
   @Test
+  public void testGetReachableLabelsWithDefaultValues() throws Exception {
+    Rule rule = createRule("a", "myrule",
+        "cc_binary(name = 'myrule',",
+        "    srcs = [],",
+        "    malloc = select({",
+        "        '//conditions:a': None,",
+        "    }))");
+
+    AggregatingAttributeMapper mapper = AggregatingAttributeMapper.of(rule);
+    assertThat(mapper.getReachableLabels("malloc", true))
+        .containsExactly(
+            getDefaultMallocLabel(rule), Label.create("@//conditions", "a"));
+  }
+
+  @Test
   public void testDuplicateCheckOnNullValues() throws Exception {
     if (TestConstants.THIS_IS_BAZEL) {
       return;