perf: reduce concatenation, use of .extends

js/private/js_binary.bzl

@@ -522,16 +522,16 @@ def _create_launcher(ctx, log_prefix_rule_set, log_prefix_rule, fixed_args = [],
     bash_launcher, toolchain_files = _bash_launcher(ctx, nodeinfo, entry_point_path, log_prefix_rule_set, log_prefix_rule, fixed_args, fixed_env, is_windows)
     launcher = create_windows_native_launcher_script(ctx, bash_launcher) if is_windows else bash_launcher
 
-    launcher_files = [bash_launcher]
-    launcher_files.extend(toolchain_files)
+    launcher_files = [bash_launcher] + toolchain_files
     if hasattr(nodeinfo, "node"):
         if nodeinfo.node:
             launcher_files.append(nodeinfo.node)
     else:
         # TODO(3.0): drop support for deprecated toolchain attributes
-        launcher_files.extend(nodeinfo.tool_files)
+        launcher_files += nodeinfo.tool_files
 
-    launcher_files.extend(ctx.files._node_patches_files + [ctx.file._node_patches])
+    launcher_files += ctx.files._node_patches_files
+    launcher_files.append(ctx.file._node_patches)
     transitive_launcher_files = None
     if ctx.attr.include_npm:
         if hasattr(nodeinfo, "npm_sources"):
@@ -540,7 +540,7 @@ def _create_launcher(ctx, log_prefix_rule_set, log_prefix_rule, fixed_args = [],
             # TODO(3.0): drop support for deprecated toolchain attributes
             if not hasattr(nodeinfo, "npm_files"):
                 fail("include_npm requires a minimum @rules_nodejs version of 5.7.0")
-            launcher_files.extend(nodeinfo.npm_files)
+            launcher_files += nodeinfo.npm_files
 
     runfiles = gather_runfiles(
         ctx = ctx,

js/private/js_helpers.bzl

@@ -182,9 +182,12 @@ def gather_runfiles(
     for target in data:
         transitive_files_depsets.append(target[DefaultInfo].files)
 
+    # Avoid concatenating more then once
+    data_deps = data + deps
+
     # Gather files from JsInfo providers of data & deps
     transitive_files_depsets.append(gather_files_from_js_infos(
-        targets = data + deps,
+        targets = data_deps,
         include_sources = include_sources,
         include_types = include_types,
         include_transitive_sources = include_transitive_sources,
@@ -209,7 +212,7 @@ def gather_runfiles(
         transitive_files = depset(transitive = transitive_files_depsets),
     ).merge_all([
         target[DefaultInfo].default_runfiles
-        for target in data + deps
+        for target in data_deps
     ])
 
 LOG_LEVELS = {

npm/private/npm_translate_lock_generate.bzl

@@ -232,11 +232,11 @@ def npm_link_all_packages(name = "node_modules", imported_links = []):
 
     for link_fn in imported_links:
         new_link_targets, new_scope_targets = link_fn(name)
-        link_targets.extend(new_link_targets)
+        link_targets += new_link_targets
         for _scope, _targets in new_scope_targets.items():
             if _scope not in scope_targets:
                 scope_targets[_scope] = []
-            scope_targets[_scope].extend(_targets)
+            scope_targets[_scope] += _targets
 """.format(
             defs_bzl_file = "@{}//:{}".format(rctx.name, rctx.attr.defs_bzl_filename),
             link_packages_comma_separated = "\"'\" + \"', '\".join(_LINK_PACKAGES) + \"'\"" if len(link_packages) else "\"\"",
@@ -346,7 +346,7 @@ def npm_link_all_packages(name = "node_modules", imported_links = []):
 
     if len(stores_bzl) > 0:
         npm_link_all_packages_bzl.append("""    if is_root:""")
-        npm_link_all_packages_bzl.extend(stores_bzl)
+        npm_link_all_packages_bzl += stores_bzl
 
     if len(links_bzl) > 0:
         npm_link_all_packages_bzl.append("""    if link:""")
@@ -356,7 +356,7 @@ def npm_link_all_packages(name = "node_modules", imported_links = []):
                 els = "" if first_link else "el",
                 pkg = link_package,
             ))
-            npm_link_all_packages_bzl.extend(bzl)
+            npm_link_all_packages_bzl += bzl
             first_link = False
 
     if len(links_targets_bzl) > 0:
@@ -367,7 +367,7 @@ def npm_link_all_packages(name = "node_modules", imported_links = []):
                 els = "" if first_link else "el",
                 pkg = link_package,
             ))
-            npm_link_targets_bzl.extend(bzl)
+            npm_link_targets_bzl += bzl
             first_link = False
 
     for fp_link in fp_links.values():
@@ -470,7 +470,7 @@ def npm_link_all_packages(name = "node_modules", imported_links = []):
                     other_statements.append(content)
             rctx_files[filename] = load_statements + rctx_files[filename] + other_statements
         else:
-            rctx_files[filename].extend(contents)
+            rctx_files[filename] += contents
 
     if not rctx.attr.bzlmod:
         rctx_files[rctx.attr.repositories_bzl_filename] = _generate_repositories(

npm/private/npm_translate_lock_helpers.bzl

@@ -57,7 +57,7 @@ def _gather_values_from_matching_names(additive, keyed_lists, *names):
             v = keyed_lists[name]
             if additive:
                 if type(v) == "list":
-                    result.extend(v)
+                    result += v
                 elif type(v) == "string":
                     result.append(v)
                 else:
@@ -352,7 +352,7 @@ ERROR: can not apply both `pnpm.patchedDependencies` and `npm_translate_lock(pat
         elif len(translate_patches) > 0:
             patches = translate_patches
             patch_args, _ = _gather_values_from_matching_names(False, attr.patch_args, "*", name, friendly_name, unfriendly_name)
-            patches_used.extend(patches_keys)
+            patches_used += patches_keys
 
         # Resolve string patch labels relative to the root respository rather than relative to rules_js.
         # https://docs.google.com/document/d/1N81qfCa8oskCk5LqTW-LNthy6EBrDot7bdUsjz6JFC4/