Bash,runfiles: ignore RUNFILES_MANIFEST_ONLY

The Bash runfiles library now ignores
$RUNFILES_MANIFEST_ONLY, instead it checks if the
requested runfile exists either under
$RUNFILES_DIR or under the path that
$RUNFILES_MANIFEST_FILE associates it with.

In this sense, the library now reflects "reality"
(returns the file if it exists) rather than a
"promise" (returns paths based on faith in
envvars).

See https://github.com/bazelbuild/bazel/issues/4460

Change-Id: Idbcfede0757e4b8217313b234c94c88bfd780691
PiperOrigin-RevId: 194388639

2 files changed, 80 insertions, 79 deletions

diff --git a/tools/bash/runfiles/runfiles.bash b/tools/bash/runfiles/runfiles.bash
index b5e3416f7a..8dd82e23b4 100644
--- a/tools/bash/runfiles/runfiles.bash
+++ b/tools/bash/runfiles/runfiles.bash
@@ -15,12 +15,9 @@
 # This Bash script defines functions to handle sh_binary/sh_test runfiles.
 #
 # REQUIREMENTS:
-# - The RUNFILES_MANIFEST_FILE and/or the RUNFILES_DIR environment variable must
-#   be set to the absolute path of the runfiles manifest or the
-#   <rulename>.runfiles directory, respectively.
-# - If RUNFILES_MANIFEST_ONLY=1 is set, then RUNFILES_MANIFEST_FILE must be set
-#   to the absolute path of the runfiles manifest. RUNFILES_DIR may be unset in
-#   this case.
+# - At least one of RUNFILES_MANIFEST_FILE and RUNFILES_DIR environment
+#   variables must be set, to the absolute path of the runfiles manifest or the
+#   <rulename>.runfiles directory respectively.
 # - If RUNFILES_LIB_DEBUG=1 is set, the script will print errors to stderr.
 #
 # USAGE:
@@ -39,22 +36,20 @@
 #
 #      set -euo pipefail
 #      # --- begin runfiles.bash initialization ---
-#      if [[ "${RUNFILES_MANIFEST_ONLY:-}" != 1 && -z "${RUNFILES_DIR:-}" ]]; then
-#        if [[ -f "$0.runfiles_manifest" ]]; then
-#          export RUNFILES_MANIFEST_ONLY=1
-#          export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
-#        elif [[ -f "$0.runfiles/MANIFEST" ]]; then
-#          export RUNFILES_MANIFEST_ONLY=1
-#          export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
-#        elif [[ -d "$0.runfiles" ]]; then
-#          export RUNFILES_DIR="$0.runfiles"
-#        fi
+#      if [[ ! -d "${RUNFILES_DIR:-/dev/null}" && ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+#          if [[ -f "$0.runfiles_manifest" ]]; then
+#            export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
+#          elif [[ -f "$0.runfiles/MANIFEST" ]]; then
+#            export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
+#          elif [[ -f "$0.runfiles/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
+#            export RUNFILES_DIR="$0.runfiles"
+#          fi
 #      fi
-#      if [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 && -f "${RUNFILES_MANIFEST_FILE:-}" ]]; then
+#      if [[ -f "${RUNFILES_DIR:-/dev/null}/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
+#        source "${RUNFILES_DIR}/bazel_tools/tools/bash/runfiles/runfiles.bash"
+#      elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
 #        source "$(grep -m1 "^bazel_tools/tools/bash/runfiles/runfiles.bash " \
 #                  "$RUNFILES_MANIFEST_FILE" | cut -d ' ' -f 2-)"
-#      elif [[ -n "${RUNFILES_DIR:-}" && -d "${RUNFILES_DIR}" ]]; then
-#        source "${RUNFILES_DIR}/bazel_tools/tools/bash/runfiles/runfiles.bash"
 #      else
 #        echo >&2 "ERROR: cannot find @bazel_tools//tools/bash/runfiles:runfiles.bash"
 #        exit 1
@@ -89,28 +84,15 @@ function rlocation() {
     fi
     return 1
   else
-    if [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 ]]; then
-      if [[ -n "${RUNFILES_MANIFEST_FILE:-}" \
-            && -f "${RUNFILES_MANIFEST_FILE}" ]]; then
-        grep -m1 "^$1 " "${RUNFILES_MANIFEST_FILE}" | cut -d ' ' -f 2- \
-          || return 1
-      else
-        if [[ "${RUNFILES_LIB_DEBUG:-}" == 1 ]]; then
-          echo >&2 "ERROR[runfiles.bash]: trying to use manifest-based" \
-                   "runfiles but RUNFILES_MANIFEST_FILE is unset or" \
-                   "non-existent" \
-                   "(RUNFILES_MANIFEST_ONLY=\"${RUNFILES_MANIFEST_ONLY:-}\"," \
-                   "RUNFILES_DIR=\"${RUNFILES_DIR:-}\")"
-        fi
-        return 1
-      fi
-    elif [[ -n "${RUNFILES_DIR:-}" && -d "${RUNFILES_DIR}" ]]; then
+    if [[ -f "${RUNFILES_DIR:-/dev/null}/$1" ]]; then
       echo "${RUNFILES_DIR}/$1"
+    elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+      local -r result=$(grep -m1 "^$1 " "${RUNFILES_MANIFEST_FILE}" | cut -d ' ' -f 2-)
+      [[ -f "${result:-/dev/null}" ]] && echo "$result" || echo ""
     else
       if [[ "${RUNFILES_LIB_DEBUG:-}" == 1 ]]; then
-        echo >&2 "ERROR[runfiles.bash]: trying to use directory-based" \
-                 "runfiles but RUNFILES_DIR is unset or non-existent" \
-                 "(RUNFILES_MANIFEST_ONLY=\"${RUNFILES_MANIFEST_ONLY:-}\"," \
+        echo >&2 "ERROR[runfiles.bash]: cannot look up runfile \"$1\" " \
+                 "(RUNFILES_DIR=\"${RUNFILES_DIR:-}\"," \
                  "RUNFILES_MANIFEST_FILE=\"${RUNFILES_MANIFEST_FILE:-}\")"
       fi
       return 1
@@ -119,31 +101,37 @@ function rlocation() {
 }
 export -f rlocation
 
-# Exports the environment variables that subprocesses may need to use runfiles.
+# Exports the environment variables that subprocesses need in order to use
+# runfiles.
 # If a subprocess is a Bazel-built binary rule that also uses the runfiles
-# libraries under @bazel_tools//tools/bash/runfiles, then that binary needs
+# libraries under @bazel_tools//tools/<lang>/runfiles, then that binary needs
 # these envvars in order to initialize its own runfiles library.
 function runfiles_export_envvars() {
-  if [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 ]]; then
-    if [[ -z "${RUNFILES_MANIFEST_FILE:-}" \
-          && ! -f "$RUNFILES_MANIFEST_FILE" ]]; then
-      return 1
+  if [[ ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" \
+        && ! -d "${RUNFILES_DIR:-/dev/null}" ]]; then
+    return 1
+  fi
+
+  if [[ ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+    if [[ -f "$RUNFILES_DIR/MANIFEST" ]]; then
+      export RUNFILES_MANIFEST_FILE="$RUNFILES_DIR/MANIFEST"
+    elif [[ -f "${RUNFILES_DIR}_manifest" ]]; then
+      export RUNFILES_MANIFEST_FILE="${RUNFILES_DIR}_manifest"
+    else
+      export RUNFILES_MANIFEST_FILE=
     fi
-    if [[ -z "${RUNFILES_DIR:-}" ]]; then
-      if [[ "$RUNFILES_MANIFEST_FILE" == */MANIFEST \
-            && -d "${RUNFILES_MANIFEST_FILE%/MANIFEST}" ]]; then
-        export RUNFILES_DIR="${RUNFILES_MANIFEST_FILE%/MANIFEST}"
-      elif [[ "$RUNFILES_MANIFEST_FILE" == *runfiles_manifest \
-            && -d "${RUNFILES_MANIFEST_FILE%_manifest}" ]]; then
-        export RUNFILES_DIR="${RUNFILES_MANIFEST_FILE%_manifest}"
-      fi
+  elif [[ ! -d "${RUNFILES_DIR:-/dev/null}" ]]; then
+    if [[ "$RUNFILES_MANIFEST_FILE" == */MANIFEST \
+          && -d "${RUNFILES_MANIFEST_FILE%/MANIFEST}" ]]; then
+      export RUNFILES_DIR="${RUNFILES_MANIFEST_FILE%/MANIFEST}"
+      export JAVA_RUNFILES="$RUNFILES_DIR"
+    elif [[ "$RUNFILES_MANIFEST_FILE" == *_manifest \
+          && -d "${RUNFILES_MANIFEST_FILE%_manifest}" ]]; then
+      export RUNFILES_DIR="${RUNFILES_MANIFEST_FILE%_manifest}"
+      export JAVA_RUNFILES="$RUNFILES_DIR"
+    else
+      export RUNFILES_DIR=
     fi
   fi
-  # No need to define anything if RUNFILES_MANIFEST_ONLY is not 1: it makes no
-  # difference whether RUNFILES_DIR is defined or not.
-
-  export RUNFILES_MANIFEST_FILE="${RUNFILES_MANIFEST_FILE:-}"
-  export RUNFILES_DIR="${RUNFILES_DIR:-}"
-  export JAVA_RUNFILES="${RUNFILES_DIR:-}"
 }
 export -f runfiles_export_envvars
diff --git a/tools/bash/runfiles/runfiles_test.bash b/tools/bash/runfiles/runfiles_test.bash
index 0c1211c310..88ba63cd9d 100755
--- a/tools/bash/runfiles/runfiles_test.bash
+++ b/tools/bash/runfiles/runfiles_test.bash
@@ -53,14 +53,23 @@ function find_runfiles_lib() {
     unset runfiles_export_envvars
   fi
 
-  if [[ "${RUNFILES_MANIFEST_ONLY:-}" == "1" ]]; then
-    grep -m1 "^io_bazel/tools/bash/runfiles/runfiles.bash" \
-             "${RUNFILES_MANIFEST_FILE}" | cut -d ' ' -f 2-
-  elif [[ -n "${RUNFILES_DIR:-}" && -d "$RUNFILES_DIR" ]]; then
+  if [[ ! -d "${RUNFILES_DIR:-/dev/null}" && ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+    if [[ -f "$0.runfiles_manifest" ]]; then
+      export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
+    elif [[ -f "$0.runfiles/MANIFEST" ]]; then
+      export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
+    elif [[ -f "$0.runfiles/io_bazel/tools/bash/runfiles/runfiles.bash" ]]; then
+      export RUNFILES_DIR="$0.runfiles"
+    fi
+  fi
+  if [[ -f "${RUNFILES_DIR:-/dev/null}/io_bazel/tools/bash/runfiles/runfiles.bash" ]]; then
     echo "${RUNFILES_DIR}/io_bazel/tools/bash/runfiles/runfiles.bash"
+  elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+    grep -m1 "^io_bazel/tools/bash/runfiles/runfiles.bash " \
+        "$RUNFILES_MANIFEST_FILE" | cut -d ' ' -f 2-
   else
     echo >&2 "ERROR: cannot find //tools/bash/runfiles:runfiles.bash"
-    return 1
+    exit 1
   fi
 }
 
@@ -126,20 +135,24 @@ function test_rlocation_abs_path() {
 
 function test_init_manifest_based_runfiles() {
   local tmpdir="$(mktemp -d $TEST_TMPDIR/tmp.XXXXXXXX)"
-  cat > $tmpdir/foo.runfiles_manifest << 'EOF'
-a/b c/d
-e/f g h
+  cat > $tmpdir/foo.runfiles_manifest << EOF
+a/b $tmpdir/c/d
+e/f $tmpdir/g h
 EOF
+  mkdir "${tmpdir}/c"
+  touch "${tmpdir}/c/d" "${tmpdir}/g h"
 
   export RUNFILES_DIR=
   export RUNFILES_MANIFEST_FILE=$tmpdir/foo.runfiles_manifest
-  export RUNFILES_MANIFEST_ONLY=1
   source "$runfiles_lib_path"
 
   [[ -z "$(rlocation a)" ]] || fail
-  [[ "$(rlocation a/b)" == "c/d" ]] || fail
-  [[ "$(rlocation e/f)" == "g h" ]] || fail
   [[ -z "$(rlocation c/d)" ]] || fail
+  [[ "$(rlocation a/b)" == "$tmpdir/c/d" ]] || fail
+  [[ "$(rlocation e/f)" == "$tmpdir/g h" ]] || fail
+  rm "$tmpdir/c/d" "$tmpdir/g h"
+  [[ -z "$(rlocation a/b)" ]] || fail
+  [[ -z "$(rlocation e/f)" ]] || fail
 }
 
 function test_manifest_based_envvars() {
@@ -148,14 +161,12 @@ function test_manifest_based_envvars() {
 
   export RUNFILES_DIR=
   export RUNFILES_MANIFEST_FILE=$tmpdir/foo.runfiles_manifest
-  export RUNFILES_MANIFEST_ONLY=1
   mkdir -p $tmpdir/foo.runfiles
   source "$runfiles_lib_path"
 
   runfiles_export_envvars
   [[ "${RUNFILES_DIR:-}" == "$tmpdir/foo.runfiles" ]] || fail
   [[ "${RUNFILES_MANIFEST_FILE:-}" == "$tmpdir/foo.runfiles_manifest" ]] || fail
-  [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 ]] || fail
 }
 
 function test_init_directory_based_runfiles() {
@@ -163,28 +174,31 @@ function test_init_directory_based_runfiles() {
 
   export RUNFILES_DIR=${tmpdir}/mock/runfiles
   export RUNFILES_MANIFEST_FILE=
-  export RUNFILES_MANIFEST_ONLY=
   source "$runfiles_lib_path"
 
-  mkdir -p "$RUNFILES_DIR"
-  [[ "$(rlocation a)" == */mock/runfiles/a ]] || fail
-  [[ "$(rlocation a/b)" == *mock/runfiles/a/b ]] || fail
+  mkdir -p "$RUNFILES_DIR/a"
+  touch "$RUNFILES_DIR/a/b" "$RUNFILES_DIR/c d"
+  [[ -z "$(rlocation a)" ]] || fail
+  [[ -z "$(rlocation c/d)" ]] || fail
+  [[ "$(rlocation a/b)" == "$RUNFILES_DIR/a/b" ]] || fail
+  [[ "$(rlocation "c d")" == "$RUNFILES_DIR/c d" ]] || fail
+  [[ -z "$(rlocation "c")" ]] || fail
+  rm "$RUNFILES_DIR/a/b" "$RUNFILES_DIR/c d"
+  [[ -z "$(rlocation a/b)" ]] || fail
+  [[ -z "$(rlocation "c d")" ]] || fail
 }
 
 function test_directory_based_envvars() {
   export RUNFILES_DIR=mock/runfiles
   export RUNFILES_MANIFEST_FILE=
-  export RUNFILES_MANIFEST_ONLY=
   source "$runfiles_lib_path"
 
   runfiles_export_envvars
   [[ "${RUNFILES_DIR:-}" == "mock/runfiles" ]] || fail
   [[ -z "${RUNFILES_MANIFEST_FILE:-}" ]] || fail
-  [[ -z "${RUNFILES_MANIFEST_ONLY:-}" ]] || fail
 }
 
 function main() {
-  local -r manifest_only="${RUNFILES_MANIFEST_ONLY:-}"
   local -r manifest_file="${RUNFILES_MANIFEST_FILE:-}"
   local -r dir="${RUNFILES_DIR:-}"
   local -r runfiles_lib_path=$(find_runfiles_lib)
@@ -192,7 +206,6 @@ function main() {
   local -r tests=$(declare -F | grep " -f test" | awk '{print $3}')
   local failure=0
   for t in $tests; do
-    export RUNFILES_MANIFEST_ONLY="$manifest_only"
     export RUNFILES_MANIFEST_FILE="$manifest_file"
     export RUNFILES_DIR="$dir"
     if ! ($t); then