Do not crash tests when one of the {JAVA,PYTHON}_RUNFILES variables…

… is overridden.

Environment collection uses `ImmutableMap.Builder::buildOrThrow` for the variables map which will crash when user specifies only one of the runfiles variables on the command line. Change the logic to pick up the values specified by the user instead.

PiperOrigin-RevId: 446207370

src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java

@@ -85,12 +85,12 @@ public ImmutableMap<String, String> getEnvironment() {
       return environment;
     } else {
       ImmutableMap.Builder<String, String> env = ImmutableMap.builder();
-      env.putAll(environment);
       // TODO(bazel-team): Unify these into a single env variable.
       String runfilesRootString = runfilesRoot.getPathString();
       env.put("JAVA_RUNFILES", runfilesRootString);
       env.put("PYTHON_RUNFILES", runfilesRootString);
-      return env.buildOrThrow();
+      env.putAll(environment);
+      return env.buildKeepingLast();
     }
   }
 

src/test/java/com/google/devtools/build/lib/buildtool/util/BuildIntegrationTestCase.java

@@ -613,7 +613,7 @@ protected Path getExecutableLocation(String target)
    *
    * @param target the label of the target whose artifacts are requested.
    */
-  protected Iterable<Artifact> getArtifacts(String target)
+  protected ImmutableList<Artifact> getArtifacts(String target)
       throws LabelSyntaxException, NoSuchPackageException, NoSuchTargetException,
           InterruptedException, TransitionException, InvalidConfigurationException {
     return getFilesToBuild(getConfiguredTarget(target)).toList();

src/test/shell/bazel/bazel_test_test.sh

@@ -144,6 +144,38 @@ EOF
   expect_log "ws: bar$"
 }
 
+function test_runfiles_java_runfiles_merges_env_vars() {
+  runfiles_merges_runfiles_env_vars JAVA_RUNFILES PYTHON_RUNFILES
+}
+
+function test_runfiles_python_runfiles_merges_env_vars() {
+  runfiles_merges_runfiles_env_vars PYTHON_RUNFILES JAVA_RUNFILES
+}
+
+# Usage: runfiles_merges_runfiles_env_vars overridden unchanged
+function runfiles_merges_runfiles_env_vars() {
+  local -r overridden=$1
+  local -r unchanged=$2
+  cat > WORKSPACE <<EOF
+workspace(name = "bar")
+EOF
+  add_rules_cc_to_workspace WORKSPACE
+  mkdir -p foo
+  cat > foo/foo.sh <<'EOF'
+#!/bin/sh
+echo "JAVA_RUNFILES: ${JAVA_RUNFILES}"
+echo "PYTHON_RUNFILES: ${PYTHON_RUNFILES}"
+EOF
+  chmod +x foo/foo.sh
+  echo 'sh_test(name = "foo", srcs = ["foo.sh"])' > foo/BUILD
+
+  bazel test --test_env="${overridden}"=override --test_output=all \
+      //foo >& "${TEST_log}" || fail "Test failed"
+
+  expect_log "${overridden}: /.*/execroot/bar/override"
+  expect_log "${unchanged}: /.*/execroot/bar/bazel-out/[^/]\+-fastbuild/bin/foo/foo.runfiles"
+}
+
 function test_run_under_external_label_with_options() {
   mkdir -p testing run || fail "mkdir testing run failed"
   cat <<EOF > run/BUILD