[surface-ui#481] Disable build timestamp, replace header

This change removes the build timestamp from headers of the generated
files, and replaces it with a helpful message pointing to the original
source files that should be modified instead of the current file.

This change also improves the tests by generating the hook files in the
tests themselves, making sure their content changes and not just rely on
the timestamps / build times.

.gitignore

@@ -23,4 +23,8 @@ erl_crash.dump
 surface-*.tar
 
 # Ignore temp files.
-/tmp/
+/tmp/
+
+# Ignore fake hooks files that are created in tests
+/test/support/mix/tasks/compile/surface_test/fake_button.hooks.js
+/test/support/mix/tasks/compile/surface_test/fake_link.hooks.js

lib/mix/tasks/compile/surface.ex

@@ -10,17 +10,15 @@ defmodule Mix.Tasks.Compile.Surface do
   @hooks_extension ".hooks.js"
 
   @doc false
-  def run(args) do
-    build_time = Keyword.get(args, :build_time)
-
-    case get_colocated_assets() |> generate_files(build_time) do
+  def run(_args) do
+    case get_colocated_assets() |> generate_files() do
       "" -> {:noop, []}
       _ -> {:ok, []}
     end
   end
 
   @doc false
-  def generate_files({js_files, _css_files}, build_time \\ nil) do
+  def generate_files({js_files, _css_files}) do
     opts = Application.get_env(:surface, :compiler, [])
 
     hooks_output_dir = Keyword.get(opts, :hooks_output_dir, @default_hooks_output_dir)
@@ -44,13 +42,13 @@ defmodule Mix.Tasks.Compile.Surface do
           !File.exists?(dest_file) or time > index_file_time,
           reduce: false do
         _ ->
-          content = [header(build_time), "\n\n", File.read!(src_file)]
+          content = [header(src_file), "\n\n", File.read!(src_file)]
           File.write!(dest_file, content)
           true
       end
 
     if !index_file_time or update_index? or unused_hooks_files != [] do
-      File.write!(index_file, index_content(js_files, build_time))
+      File.write!(index_file, index_content(js_files))
     end
   end
 
@@ -76,15 +74,15 @@ defmodule Mix.Tasks.Compile.Surface do
     end
   end
 
-  defp index_content([], build_time) do
+  defp index_content([]) do
     """
-    #{header(build_time)}
+    #{header()}
 
     export default {}
     """
   end
 
-  defp index_content(js_files, build_time) do
+  defp index_content(js_files) do
     files = js_files |> Enum.sort() |> Enum.with_index(1)
 
     {hooks, imports} =
@@ -101,7 +99,7 @@ defmodule Mix.Tasks.Compile.Surface do
     imports = Enum.reverse(imports)
 
     """
-    #{header(build_time)}
+    #{header()}
 
     function ns(hooks, nameSpace) {
       const updatedHooks = {}
@@ -166,14 +164,23 @@ defmodule Mix.Tasks.Compile.Surface do
     match?({:module, _mod}, Code.ensure_compiled(module))
   end
 
-  defp header(build_time) do
-    build_time = build_time || DateTime.utc_now()
+  defp header() do
+    """
+    /*
+    This file was generated by the Surface compiler.
+
+    Please do not modify this file directly.
+    */\
+    """
+  end
 
+  defp header(src_file) do
     """
     /*
     This file was generated by the Surface compiler.
 
-    Build time: #{build_time}
+    Please do not modify this file directly, instead edit the source file:
+    #{src_file |> Path.relative_to_cwd()}
     */\
     """
   end

test/mix/tasks/compile/surface_test.exs

@@ -8,19 +8,24 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
   @test_components_dir Path.join(File.cwd!(), "test/support/mix/tasks/compile/surface_test")
 
   @button_src_hooks_file Path.join(@test_components_dir, "fake_button.hooks.js")
+  @button_rel_src_hooks_file Path.join("test/support/mix/tasks/compile/surface_test", "fake_button.hooks.js")
   @button_dest_hooks_file Path.join(
                             @hooks_output_dir,
                             "Mix.Tasks.Compile.SurfaceTest.FakeButton.hooks.js"
                           )
+  @button_src_hooks_file_content "let FakeButton = {}\nexport { FakeButton }"
+  @button_src_hooks_file_content_modified "let FakeButton = { mounted() {} }\nexport { FakeButton }"
+
+  @link_src_hooks_file Path.join(@test_components_dir, "fake_link.hooks.js")
+  @link_rel_src_hooks_file Path.join("test/support/mix/tasks/compile/surface_test", "fake_link.hooks.js")
   @link_dest_hooks_file Path.join(
                           @hooks_output_dir,
                           "Mix.Tasks.Compile.SurfaceTest.FakeLink.hooks.js"
                         )
+  @link_src_hooks_file_content "let FakeLink = {}\nexport { FakeLink }"
 
   @hooks_index_file Path.join(@hooks_output_dir, "index.js")
 
-  @build_time DateTime.new!(~D[2021-01-01], ~T[20:01:02.000003])
-
   setup_all do
     conf_before = Application.get_env(:surface, :compiler, [])
     Application.put_env(:surface, :compiler, hooks_output_dir: @hooks_rel_output_dir)
@@ -33,12 +38,17 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
   end
 
   setup do
+    File.write!(@button_src_hooks_file, @button_src_hooks_file_content)
+    File.write!(@link_src_hooks_file, @link_src_hooks_file_content)
+
     if File.exists?(@hooks_output_dir) do
       File.rm_rf!(@hooks_output_dir)
     end
 
     on_exit(fn ->
       File.rm_rf!(@hooks_output_dir)
+      File.rm_rf!(@button_src_hooks_file)
+      File.rm_rf!(@link_src_hooks_file)
     end)
 
     :ok
@@ -48,13 +58,14 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
     refute File.exists?(@button_dest_hooks_file)
     refute File.exists?(@link_dest_hooks_file)
 
-    run(build_time: @build_time)
+    run([])
 
     assert File.read!(@button_dest_hooks_file) == """
            /*
            This file was generated by the Surface compiler.
 
-           Build time: 2021-01-01 20:01:02.000003Z
+           Please do not modify this file directly, instead edit the source file:
+           #{@button_rel_src_hooks_file}
            */
 
            let FakeButton = {}
@@ -65,7 +76,8 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
            /*
            This file was generated by the Surface compiler.
 
-           Build time: 2021-01-01 20:01:02.000003Z
+           Please do not modify this file directly, instead edit the source file:
+           #{@link_rel_src_hooks_file}
            */
 
            let FakeLink = {}
@@ -76,13 +88,13 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
   test "generate index.js file for hooks" do
     refute File.exists?(@hooks_output_dir)
 
-    run(build_time: @build_time)
+    run([])
 
     assert File.read!(@hooks_index_file) =~ """
            /*
            This file was generated by the Surface compiler.
 
-           Build time: 2021-01-01 20:01:02.000003Z
+           Please do not modify this file directly.
            */
 
            function ns(hooks, nameSpace) {
@@ -105,7 +117,7 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
            """
   end
 
-  test "update dest hook file and index.js if src hook file is newer then index.js" do
+  test "update dest hook file and index.js if src hook file is newer than index.js" do
     refute File.exists?(@hooks_output_dir)
 
     run([])
@@ -115,40 +127,42 @@ defmodule Mix.Tasks.Compile.SurfaceTest do
     assert files_changed?(files, fn -> run([]) end) == [false, false, false]
 
     mtime = @hooks_index_file |> get_mtime() |> inc_mtime()
+    File.write!(@button_src_hooks_file, @button_src_hooks_file_content_modified)
     File.touch!(@button_src_hooks_file, mtime)
 
-    assert files_changed?(files, fn -> run([]) end) == [true, false, true]
+    assert files_changed?(files, fn -> run([]) end) == [true, false, false]
+
+    assert File.read!(@button_dest_hooks_file) =~ "let FakeButton = { mounted() {} }"
   end
 
   test "generate index.js with empty object if there's no hooks available" do
     refute File.exists?(@hooks_output_dir)
 
-    generate_files({[], []}, @build_time)
+    generate_files({[], []})
 
     assert File.read!(@hooks_index_file) == """
            /*
            This file was generated by the Surface compiler.
 
-           Build time: 2021-01-01 20:01:02.000003Z
+           Please do not modify this file directly.
            */
 
            export default {}
            """
   end
 
-  test "delete unused hooks files from output dir and update index.js" do
+  test "removes unused hooks files from output dir and update index.js" do
     refute File.exists?(@hooks_output_dir)
 
     run([])
 
-    unused_file = Path.join(@hooks_output_dir, "Unused.hooks.js")
-    File.touch!(unused_file)
+    assert File.exists?(@link_dest_hooks_file)
 
-    assert File.exists?(unused_file)
+    File.rm!(@link_src_hooks_file)
 
     assert files_changed?([@hooks_index_file], fn -> run([]) end) == [true]
 
-    refute File.exists?(unused_file)
+    refute File.exists?(@link_dest_hooks_file)
   end
 
   defp inc_mtime(time) do