Introduce a new SkyValue that merely contains the workspace name. The workspace name is needed for package loading, and so splitting out this computation into a separate skyframe node that can be change-pruned gives us better incrementality; previously we'd need to reload all packages on a WORKSPACE file change.

N.B.
(i) This CL doesn't solve all the other performance issues with //external in Bazel/Blaze since it's still inefficiently used for resolving labels like @foo//bar:baz.
(ii) This CL doesn't address the wasteful invalidation + change pruning of all the packages.

--
PiperOrigin-RevId: 146925369
MOS_MIGRATED_REVID=146925369

1 files changed, 25 insertions, 0 deletions

diff --git a/src/test/shell/integration/loading_phase_tests.sh b/src/test/shell/integration/loading_phase_tests.sh
index cba257afbd..a318c6a20b 100755
--- a/src/test/shell/integration/loading_phase_tests.sh
+++ b/src/test/shell/integration/loading_phase_tests.sh
@@ -315,4 +315,29 @@ function test_incremental_deleting_package_roots() {
   expect_not_log "//a:external"
 }
 
+function test_no_package_loading_on_benign_workspace_file_changes() {
+  mkdir foo
+
+  echo 'workspace(name="wsname1")' > WORKSPACE
+  echo 'sh_library(name="shname1")' > foo/BUILD
+  bazel query //foo:all >& "$TEST_log" || fail "Expected success"
+  expect_log "//foo:shname1"
+
+  echo 'sh_library(name="shname2")' > foo/BUILD
+  bazel query //foo:all >& "$TEST_log" || fail "Expected success"
+  expect_log "Loading package: foo"
+  expect_log "//foo:shname2"
+
+  echo 'workspace(name="wsname1")' > WORKSPACE
+  echo '#benign comment' >> WORKSPACE
+  bazel query //foo:all >& "$TEST_log" || fail "Expected success"
+  expect_not_log "Loading package: foo"
+  expect_log "//foo:shname2"
+
+  echo 'workspace(name="wsname2")' > WORKSPACE
+  bazel query //foo:all >& "$TEST_log" || fail "Expected success"
+  expect_log "Loading package: foo"
+  expect_log "//foo:shname2"
+}
+
 run_suite "Integration tests of ${PRODUCT_NAME} using loading/analysis phases."