Provides a clearer message when target analysis fails because its dynamic

config is missing required fragments.

Before this change, Bazel crashes with the mysterious error: "Fragment
foo can't load missing options BarOptions" with no details on which target or dep
needed Foo. So figuring out the source of the error is painful.

With this change, we instead get:

  //foo:foo: dependency //bar:bar from attribute "deps" is missing required config fragments: JavaConfiguration

--
MOS_MIGRATED_REVID=129143764

1 files changed, 22 insertions, 0 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/BuildViewTest.java b/src/test/java/com/google/devtools/build/lib/analysis/BuildViewTest.java
index 3efe26b16d..8d45c93362 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/BuildViewTest.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/BuildViewTest.java
@@ -1230,6 +1230,28 @@ public class BuildViewTest extends BuildViewTestBase {
         ruleClassProvider.getUniversalFragment());
   }
 
+  @Test
+  public void errorOnMissingDepFragments() throws Exception {
+    scratch.file("foo/BUILD",
+        "cc_library(",
+        "    name = 'ccbin', ",
+        "    srcs = ['c.cc'],",
+        "    data = [':javalib'])",
+        "java_library(",
+        "    name = 'javalib',",
+        "    srcs = ['javalib.java'])");
+    useConfiguration("--experimental_dynamic_configs", "--experimental_disable_jvm");
+    reporter.removeHandler(failFastHandler);
+    try {
+      update("//foo:ccbin");
+      fail();
+    } catch (ViewCreationFailedException e) {
+      // Expected.
+    }
+    assertContainsEvent("//foo:ccbin: dependency //foo:javalib from attribute \"data\" is missing "
+        + "required config fragments: Jvm");
+  }
+
   /** Runs the same test with the reduced loading phase. */
   @TestSpec(size = Suite.SMALL_TESTS)
   @RunWith(JUnit4.class)