From 69f9ed14a9aa0313f55b348d1246891bbd310bf1 Mon Sep 17 00:00:00 2001
From: Jingwen Chen <jingwen@google.com>
Date: Wed, 16 Jun 2021 09:44:26 +0000
Subject: [PATCH] Show bazel help for `b` called without args.

This is less surprising than trying to use --config=bp2build as the only args, which is invalid.

Test: source build/envsetup.sh; b
Change-Id: I0b3724d05b8cc149268e660eb672192fe9bad19d
---
 envsetup.sh | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/envsetup.sh b/envsetup.sh
index bbb18e5f5c..c6151559c4 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -1696,12 +1696,19 @@ function _trigger_build()
     fi
 )
 
+# Convenience entry point (like m) to use Bazel in AOSP.
 function b()
 (
     # Generate BUILD, bzl files into the synthetic Bazel workspace (out/soong/workspace).
     m nothing GENERATE_BAZEL_FILES=true || return 1
     # Then, run Bazel using the synthetic workspace as the --package_path.
-    "$(gettop)/tools/bazel" "$@" --config=bp2build
+    if [[ -z "$@" ]]; then
+        # If there are no args, show help.
+        "$(gettop)/tools/bazel" help
+    else
+        # Else, always run with the bp2build configuration, which sets Bazel's package path to the synthetic workspace.
+        "$(gettop)/tools/bazel" "$@" --config=bp2build
+    fi
 )
 
 function m()