diff --git a/ts/copy.bzl b/ts/copy.bzl
index e62d7a044..2b5302671 100644
--- a/ts/copy.bzl
+++ b/ts/copy.bzl
@@ -26,3 +26,23 @@ def copy_files(ctx, files):
     )
 
     return [DefaultInfo(files = depset(outputs))]
+
+def copy_select_files(ctx, files, include, exclude, unwanted_prefix):
+    wanted = []
+    for f in files.to_list():
+        path = f.path
+        want = True
+
+        for substr in exclude:
+            if substr in path:
+                want = False
+                continue
+        if not want:
+            continue
+
+        for substr in include:
+            if substr in path:
+                output = path.replace(unwanted_prefix, "")
+                wanted.append((f, output))
+
+    return copy_files(ctx, wanted)
diff --git a/ts/css-browser-selector.bzl b/ts/css-browser-selector.bzl
index ad2c4578b..d03ee3315 100644
--- a/ts/css-browser-selector.bzl
+++ b/ts/css-browser-selector.bzl
@@ -1,4 +1,4 @@
-load("//ts:copy.bzl", "copy_files")
+load("//ts:copy.bzl", "copy_select_files")
 
 "Rule to copy css-browser-selector subset from node_modules to vendor folder."
 
@@ -9,17 +9,13 @@ _include = [
 _unwanted_prefix = "external/npm/node_modules/css-browser-selector/"
 
 def _copy_css_browser_selector_impl(ctx):
-    wanted = []
-    for f in ctx.attr.css_browser_selector.files.to_list():
-        path = f.path
-        want = True
-
-        for substr in _include:
-            if substr in path:
-                output = path.replace(_unwanted_prefix, "")
-                wanted.append((f, output))
-
-    return copy_files(ctx, wanted)
+    return copy_select_files(
+        ctx,
+        ctx.attr.css_browser_selector.files,
+        _include,
+        [],
+        _unwanted_prefix,
+    )
 
 copy_css_browser_selector = rule(
     implementation = _copy_css_browser_selector_impl,
diff --git a/ts/jquery-ui.bzl b/ts/jquery-ui.bzl
index f99e1cef7..482aa6985 100644
--- a/ts/jquery-ui.bzl
+++ b/ts/jquery-ui.bzl
@@ -1,4 +1,4 @@
-load("//ts:copy.bzl", "copy_files")
+load("//ts:copy.bzl", "copy_select_files")
 
 "Rule to copy jquery-ui subset from node_modules to vendor folder."
 
@@ -9,17 +9,13 @@ _include = [
 _unwanted_prefix = "external/npm/node_modules/jquery-ui-dist/"
 
 def _copy_jquery_ui_impl(ctx):
-    wanted = []
-    for f in ctx.attr.jquery_ui.files.to_list():
-        path = f.path
-        want = True
-
-        for substr in _include:
-            if substr in path:
-                output = path.replace(_unwanted_prefix, "")
-                wanted.append((f, output))
-
-    return copy_files(ctx, wanted)
+    return copy_select_files(
+        ctx,
+        ctx.attr.jquery_ui.files,
+        _include,
+        [],
+        _unwanted_prefix,
+    )
 
 copy_jquery_ui = rule(
     implementation = _copy_jquery_ui_impl,
diff --git a/ts/jquery.bzl b/ts/jquery.bzl
index 86025d04a..f7a3542d8 100644
--- a/ts/jquery.bzl
+++ b/ts/jquery.bzl
@@ -1,4 +1,4 @@
-load("//ts:copy.bzl", "copy_files")
+load("//ts:copy.bzl", "copy_select_files")
 
 "Rule to copy jquery subset from node_modules to vendor folder."
 
@@ -9,17 +9,13 @@ _include = [
 _unwanted_prefix = "external/npm/node_modules/jquery/dist/"
 
 def _copy_jquery_impl(ctx):
-    wanted = []
-    for f in ctx.attr.jquery.files.to_list():
-        path = f.path
-        want = True
-
-        for substr in _include:
-            if substr in path:
-                output = path.replace(_unwanted_prefix, "")
-                wanted.append((f, output))
-
-    return copy_files(ctx, wanted)
+    return copy_select_files(
+        ctx,
+        ctx.attr.jquery.files,
+        _include,
+        [],
+        _unwanted_prefix,
+    )
 
 copy_jquery = rule(
     implementation = _copy_jquery_impl,
diff --git a/ts/mathjax.bzl b/ts/mathjax.bzl
index 81f22365c..f50d3cf81 100644
--- a/ts/mathjax.bzl
+++ b/ts/mathjax.bzl
@@ -1,11 +1,7 @@
-load("//ts:copy.bzl", "copy_files")
+load("//ts:copy.bzl", "copy_select_files")
 
 "Rule to copy mathjax subset from node_modules to vendor folder."
 
-_exclude = [
-    "mathmaps_ie.js",
-]
-
 _include = [
     "es5/tex-chtml.js",
     "es5/input/tex/extensions",
@@ -14,26 +10,20 @@ _include = [
     "es5/sre",
 ]
 
+_exclude = [
+    "mathmaps_ie.js",
+]
+
 _unwanted_prefix = "external/npm/node_modules/mathjax/es5/"
 
 def _copy_mathjax_impl(ctx):
-    wanted = []
-    for f in ctx.attr.mathjax.files.to_list():
-        path = f.path
-        want = True
-        for substr in _exclude:
-            if substr in path:
-                want = False
-                continue
-        if not want:
-            continue
-
-        for substr in _include:
-            if substr in path:
-                output = path.replace(_unwanted_prefix, "")
-                wanted.append((f, output))
-
-    return copy_files(ctx, wanted)
+    return copy_select_files(
+        ctx,
+        ctx.attr.mathjax.files,
+        _include,
+        _exclude,
+        _unwanted_prefix,
+    )
 
 copy_mathjax = rule(
     implementation = _copy_mathjax_impl,
diff --git a/ts/protobufjs.bzl b/ts/protobufjs.bzl
index 218d2ac65..80a26f26c 100644
--- a/ts/protobufjs.bzl
+++ b/ts/protobufjs.bzl
@@ -1,4 +1,4 @@
-load("//ts:copy.bzl", "copy_files")
+load("//ts:copy.bzl", "copy_select_files")
 
 "Rule to copy protobufjs subset from node_modules to vendor folder."
 
@@ -9,17 +9,13 @@ _include = [
 _unwanted_prefix = "external/npm/node_modules/protobufjs/dist/"
 
 def _copy_protobufjs_impl(ctx):
-    wanted = []
-    for f in ctx.attr.protobufjs.files.to_list():
-        path = f.path
-        want = True
-
-        for substr in _include:
-            if substr in path:
-                output = path.replace(_unwanted_prefix, "")
-                wanted.append((f, output))
-
-    return copy_files(ctx, wanted)
+    return copy_select_files(
+        ctx,
+        ctx.attr.protobufjs.files,
+        _include,
+        [],
+        _unwanted_prefix,
+    )
 
 copy_protobufjs = rule(
     implementation = _copy_protobufjs_impl,