feat: add BAZEL env variable to js_binary

js/private/js_binary.bzl

@@ -34,6 +34,10 @@ Bazel option to see more detail about the selection.
 All [common binary attributes](https://bazel.build/reference/be/common-definitions#common-attributes-binaries) are supported
 including `args` as the list of arguments passed Node.js.
 
+`js_binary` always sets the `BAZEL` environment variable to `1`, if it is not already set, which can be used by Node.js
+programs to detect if they are running under Bazel. This can be useful for cases where a Node.js program is run both
+under Bazel and non-Bazel use cases and different code paths are required between the two.
+
 The following environment variables are made available to the Node.js runtime based on available Bazel [Make variables](https://bazel.build/reference/be/make-variables#predefined_variables):
 
 * JS_BINARY__BINDIR: the WORKSPACE-relative Bazel bin directory; equivalent to the `$(BINDIR)` Make variable of the `js_binary` target

js/private/js_binary.sh.tpl

@@ -14,6 +14,12 @@ set -o pipefail -o errexit -o nounset
 
 {{envs}}
 
+# Set BAZEL as a comment env var for all rules_js programs to be able to detect
+# they are being run under Bazel
+if [ -z "${BAZEL:-}" ]; then
+    export BAZEL=1
+fi
+
 # ==============================================================================
 # Prepare stdout capture, stderr capture && logging
 # ==============================================================================
@@ -32,10 +38,10 @@ function logf_stderr {
     local format_string="$1\n"
     shift
     if [ "${STDERR_CAPTURE:-}" ]; then
-        # shellcheck disable=SC2059
+        # shellcheck disable=SC2059,SC2046
         echo -e $(printf "$format_string" "$@") >>"$STDERR_CAPTURE"
     else
-        # shellcheck disable=SC2059
+        # shellcheck disable=SC2059,SC2046
         echo -e $(printf "$format_string" "$@") >&2
     fi
 }

js/private/test/env/BUILD.bazel

@@ -0,0 +1,6 @@
+load("//js:defs.bzl", "js_test")
+
+js_test(
+    name = "env_test",
+    entry_point = "env_test.mjs",
+)

js/private/test/env/env_test.mjs

@@ -0,0 +1,79 @@
+// Many of these env variables are set by Bazel. See https://bazel.build/reference/test-encyclopedia#initial-conditions.
+const expected = {
+    BAZEL_TEST: '1',
+    BAZEL: '1',
+    JS_BINARY__BINDIR: /^bazel-out\/[a-z0-9\-]+\/bin$/,
+    JS_BINARY__BUILD_FILE_PATH: 'js/private/test/env/BUILD.bazel',
+    JS_BINARY__COMPILATION_MODE: /.+/,
+    JS_BINARY__COPY_DATA_TO_BIN: '1',
+    JS_BINARY__EXECROOT: /.+/,
+    JS_BINARY__FS_PATCH_ROOTS: /.+/,
+    JS_BINARY__LOG_ERROR: '1',
+    JS_BINARY__LOG_FATAL: '1',
+    JS_BINARY__LOG_PREFIX: 'aspect_rules_js[js_test]',
+    JS_BINARY__NODE_BINARY: /bin\/nodejs\/bin\/node$/,
+    JS_BINARY__NODE_PATCHES_DEPTH: '.',
+    JS_BINARY__NODE_PATCHES:
+        /bazel-out\/[a-z0-9\-]+\/bin\/js\/private\/test\/env\/env_test.sh.runfiles\/[a-z_]+\/js\/private\/node-patches\/register\.js$/,
+    JS_BINARY__NODE_WRAPPER:
+        /bazel-out\/[a-z0-9\-]+\/bin\/js\/private\/test\/env\/env_test.sh.runfiles\/[a-z_]+\/js\/private\/test\/env\/env_test_node_bin\/node$/,
+    JS_BINARY__PACKAGE: 'js/private/test/env',
+    JS_BINARY__PATCH_NODE_FS: '1',
+    JS_BINARY__RUNFILES:
+        /bazel-out\/[a-z0-9\-]+\/bin\/js\/private\/test\/env\/env_test\.sh\.runfiles$/,
+    JS_BINARY__TARGET_CPU: /.+/,
+    JS_BINARY__TARGET_NAME: 'env_test',
+    JS_BINARY__TARGET: '//js/private/test/env:env_test',
+    JS_BINARY__WORKSPACE: /[a-z_]+/,
+    RUNFILES_DIR:
+        /bazel-out\/[a-z0-9\-]+\/bin\/js\/private\/test\/env\/env_test\.sh\.runfiles$/,
+    RUNFILES:
+        /bazel-out\/[a-z0-9\-]+\/bin\/js\/private\/test\/env\/env_test\.sh\.runfiles$/,
+    TEST_BINARY: 'js/private/test/env/env_test.sh',
+    TEST_INFRASTRUCTURE_FAILURE_FILE:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.infrastructure_failure$/,
+    TEST_LOGSPLITTER_OUTPUT_FILE:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.raw_splitlogs\/test\.splitlogs$/,
+    TEST_PREMATURE_EXIT_FILE:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.exited_prematurely$/,
+    TEST_SIZE: 'medium',
+    TEST_SRCDIR:
+        /bazel-out\/[a-z0-9\-]+\/bin\/js\/private\/test\/env\/env_test\.sh\.runfiles$/,
+    TEST_TARGET: '//js/private/test/env:env_test',
+    TEST_TIMEOUT: /[0-9]+/,
+    TEST_TMPDIR: /.+/,
+    TEST_UNDECLARED_OUTPUTS_ANNOTATIONS_DIR:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.outputs_manifest$/,
+    TEST_UNDECLARED_OUTPUTS_DIR:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.outputs$/,
+    TEST_UNUSED_RUNFILES_LOG_FILE:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.unused_runfiles_log$/,
+    TEST_WARNINGS_OUTPUT_FILE:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.warnings$/,
+    TEST_WORKSPACE: /[a-z_]+/,
+    XML_OUTPUT_FILE:
+        /bazel-out\/[a-z0-9\-]+\/testlogs\/js\/private\/test\/env\/env_test\/test\.xml$/,
+}
+
+let failed = false
+for (const k of Object.keys(expected)) {
+    const v = expected[k]
+    if (typeof v === 'string') {
+        if (process.env[k] !== v) {
+            console.error(
+                `Expected environment variable ${k} to equal '${v}' but got '${process.env[k]}' instead`
+            )
+            failed = true
+        }
+    } else {
+        if (!process.env[k].match(v)) {
+            console.error(
+                `Expected environment variable ${k} to match regex ${v} but value '${process.env[k]}' does not match`
+            )
+            failed = true
+        }
+    }
+}
+if (failed) {
+    process.exit(1)
+}

js/private/test/image/structure/digests.sum

@@ -1,2 +1,2 @@
-b44c02668701d4db8430edae7d6f6ecede824e704d5c46226e2b32cc20633407
+07c98625ac9e18c33bcf6d5562ab092abe470847437571e2a0b02af39932fc60
 f68066745a57eff40fc49b4600cdde860dfa86ab231ebe4ed65097c98cc2df4f

js/private/test/shellcheck_launcher.sh

@@ -25,6 +25,12 @@ export JS_BINARY__COPY_DATA_TO_BIN="1"
 if [[ -z "${JS_BINARY__LOG_FATAL:-}" ]]; then export JS_BINARY__LOG_FATAL="1"; fi
 if [[ -z "${JS_BINARY__LOG_ERROR:-}" ]]; then export JS_BINARY__LOG_ERROR="1"; fi
 
+# Set BAZEL as a comment env var for all rules_js programs to be able to detect
+# they are being run under Bazel
+if [ -z "${BAZEL:-}" ]; then
+    export BAZEL=1
+fi
+
 # ==============================================================================
 # Prepare stdout capture, stderr capture && logging
 # ==============================================================================
@@ -43,10 +49,10 @@ function logf_stderr {
     local format_string="$1\n"
     shift
     if [ "${STDERR_CAPTURE:-}" ]; then
-        # shellcheck disable=SC2059
+        # shellcheck disable=SC2059,SC2046
         echo -e $(printf "$format_string" "$@") >>"$STDERR_CAPTURE"
     else
-        # shellcheck disable=SC2059
+        # shellcheck disable=SC2059,SC2046
         echo -e $(printf "$format_string" "$@") >&2
     fi
 }