Do even less work when not importing Index Build indexstores (#3078)

Signed-off-by: Brentley Jones <github@brentleyjones.com>

xcodeproj/internal/bazel_integration_files/generate_index_build_bazel_dependencies.sh

@@ -21,35 +21,43 @@ cd "$SRCROOT"
 readonly config="${BAZEL_CONFIG}_indexbuild"
 
 # Compiled outputs (i.e. swiftmodules) and generated inputs
-readonly output_groups=(
-  "index_import"
+output_groups=(
   # Compile params
   "bc $BAZEL_TARGET_ID"
   # Products (i.e. bundles) and index store data. The products themselves aren't
   # used, they cause transitive files to be created. We use
   # `--experimental_remote_download_regex` below to collect the files we care
   # about.
   "bp $BAZEL_TARGET_ID"
-  # TODO: Remove `bi` once we remove support for legacy generation mode
-  "bi $BAZEL_TARGET_ID"
 )
 
-readonly targetid_regex='@{0,2}(.*)//(.*):(.*) ([^\ ]+)$'
-
 indexstores_filelists=()
-if [[ "$IMPORT_INDEX_BUILD_INDEXSTORES" == "YES" && \
-      "$BAZEL_TARGET_ID" =~ $targetid_regex ]]; then
-  repo="${BASH_REMATCH[1]}"
-  if [[ "$repo" == "@" ]]; then
-    repo=""
-  fi
+if [[ "$IMPORT_INDEX_BUILD_INDEXSTORES" == "YES" ]]; then
+  output_groups+=(
+    "index_import"
+    # TODO: Remove `bi` once we remove support for legacy generation mode
+    "bi $BAZEL_TARGET_ID"
+  )
+
+  readonly targetid_regex='@{0,2}(.*)//(.*):(.*) ([^\ ]+)$'
 
-  package="${BASH_REMATCH[2]}"
-  target="${BASH_REMATCH[3]}"
-  configuration="${BASH_REMATCH[4]}"
-  filelist="$configuration/bin/${repo:+"external/$repo/"}$package/$target-bi.filelist"
+  if [[ "$BAZEL_TARGET_ID" =~ $targetid_regex ]]; then
+    repo="${BASH_REMATCH[1]}"
+    if [[ "$repo" == "@" ]]; then
+      repo=""
+    fi
+
+    package="${BASH_REMATCH[2]}"
+    target="${BASH_REMATCH[3]}"
+    configuration="${BASH_REMATCH[4]}"
+    filelist="$configuration/bin/${repo:+"external/$repo/"}$package/$target-bi.filelist"
+
+    indexstores_filelists+=("$filelist")
+  fi
 
-  indexstores_filelists+=("$filelist")
+  readonly indexstores_regex='.*\.indexstore/.*|'
+else
+  readonly indexstores_regex=''
 fi
 
 readonly build_pre_config_flags=(
@@ -64,7 +72,7 @@ readonly build_pre_config_flags=(
   # This is brittle. If different file extensions are used for compilation
   # inputs, they will need to be added to this list. Ideally we can stop doing
   # this once Bazel adds support for a Remote Output Service.
-  "--experimental_remote_download_regex=.*\.indexstore/.*|.*\.(cfg|c|C|cc|cl|cpp|cu|cxx|c++|def|h|H|hh|hpp|hxx|h++|hmap|ilc|inc|inl|ipp|tcc|tlh|tli|tpp|m|modulemap|mm|pch|swift|swiftdoc|swiftmodule|swiftsourceinfo|yaml)$"
+  "--experimental_remote_download_regex=${indexstores_regex}.*|.*\.(cfg|c|C|cc|cl|cpp|cu|cxx|c++|def|h|H|hh|hpp|hxx|h++|hmap|ilc|inc|inl|ipp|tcc|tlh|tli|tpp|m|modulemap|mm|pch|swift|swiftdoc|swiftmodule|swiftsourceinfo|yaml)$"
 )
 
 source "$BAZEL_INTEGRATION_DIR/bazel_build.sh"