From 89fdc45b4540bc9d14854f2fdc7034bc0af5e2ba Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sybren=20A=2E=20St=C3=BCvel?= <sybren@blender.org>
Date: Mon, 20 Jun 2022 17:14:06 +0200
Subject: [PATCH] Manager: ignore small JS files

Empty (or almost-empty) JS files are ignored by the job compiler.
---
 .../manager/job_compilers/scripts-for-unittest/empty.js   | 0
 internal/manager/job_compilers/scripts.go                 | 8 ++++++++
 internal/manager/job_compilers/scripts_test.go            | 1 +
 3 files changed, 9 insertions(+)
 create mode 100644 internal/manager/job_compilers/scripts-for-unittest/empty.js

diff --git a/internal/manager/job_compilers/scripts-for-unittest/empty.js b/internal/manager/job_compilers/scripts-for-unittest/empty.js
new file mode 100644
index 00000000..e69de29b
diff --git a/internal/manager/job_compilers/scripts.go b/internal/manager/job_compilers/scripts.go
index c7e3c633..12d412b5 100644
--- a/internal/manager/job_compilers/scripts.go
+++ b/internal/manager/job_compilers/scripts.go
@@ -49,6 +49,14 @@ func (s *Service) loadScriptsFrom(filesystem fs.FS) error {
 			continue
 		}
 
+		if len(script_bytes) < 8 {
+			log.Debug().
+				Str("script", filename).
+				Int("fileSizeBytes", len(script_bytes)).
+				Msg("ignoring tiny JS file, it is unlikely to be a job compiler script")
+			continue
+		}
+
 		program, err := goja.Compile(filename, string(script_bytes), true)
 		if err != nil {
 			log.Error().Err(err).Str("filename", filename).Msg("failed to compile script")
diff --git a/internal/manager/job_compilers/scripts_test.go b/internal/manager/job_compilers/scripts_test.go
index 7305c963..7a614d72 100644
--- a/internal/manager/job_compilers/scripts_test.go
+++ b/internal/manager/job_compilers/scripts_test.go
@@ -25,6 +25,7 @@ func TestLoadScriptsFrom_on_disk_js(t *testing.T) {
 	expectKeys := map[string]bool{
 		"echo-and-sleep":        true,
 		"simple-blender-render": true,
+		// Should NOT contain an entry for 'empty.js'.
 	}
 	assert.Equal(t, expectKeys, keys(s.compilers))
 }