From 39dab5f2af6a5bb4f3b6f177562c4721bbb5cb22 Mon Sep 17 00:00:00 2001
From: Eric Liu <ericyl.us@gmail.com>
Date: Fri, 25 Mar 2022 20:14:13 -0700
Subject: [PATCH] [fix] ignore css-unused-selector rule if <style global>

Fixes #123
---
 src/preprocess.js                       | 7 ++++++-
 test/samples/global-style/.eslintrc.js  | 3 +++
 test/samples/global-style/Input.svelte  | 5 +++++
 test/samples/global-style/expected.json | 1 +
 4 files changed, 15 insertions(+), 1 deletion(-)
 create mode 100644 test/samples/global-style/.eslintrc.js
 create mode 100644 test/samples/global-style/Input.svelte
 create mode 100644 test/samples/global-style/expected.json

diff --git a/src/preprocess.js b/src/preprocess.js
index b03f7a5..d129281 100644
--- a/src/preprocess.js
+++ b/src/preprocess.js
@@ -73,12 +73,17 @@ export const preprocess = text => {
 	}
 	const { ast, warnings, vars, mapper } = result;
 
+  const global_style = result.ast?.css?.attributes.some(attr => attr.name === 'global');
+
 	const references_and_reassignments = `{${vars.filter(v => v.referenced || v.name[0] === '$').map(v => v.name)};${vars.filter(v => v.reassigned || v.export_name).map(v => v.name + '=0')}}`;
 	state.var_names = new Set(vars.map(v => v.name));
 
 	// convert warnings to linting messages
 	const filtered_warnings = processor_options.ignore_warnings ? warnings.filter(warning => !processor_options.ignore_warnings(warning)) : warnings;
-	state.messages = filtered_warnings.map(({ code, message, start, end }) => {
+  state.messages = filtered_warnings.filter(warning => {
+    // ignore "css-unused-selector" warnings if `<style global>`
+    return !(global_style && warning.code === 'css-unused-selector');
+  }).map(({ code, message, start, end }) => {
 		const start_pos = processor_options.typescript && start ?
 			mapper.get_original_position(start) :
 			start && { line: start.line, column: start.column + 1 };
diff --git a/test/samples/global-style/.eslintrc.js b/test/samples/global-style/.eslintrc.js
new file mode 100644
index 0000000..f8c3771
--- /dev/null
+++ b/test/samples/global-style/.eslintrc.js
@@ -0,0 +1,3 @@
+module.exports = {
+  rules: {},
+};
diff --git a/test/samples/global-style/Input.svelte b/test/samples/global-style/Input.svelte
new file mode 100644
index 0000000..56d8cfe
--- /dev/null
+++ b/test/samples/global-style/Input.svelte
@@ -0,0 +1,5 @@
+<style global>
+  h1 {
+    color: red;
+  }
+</style>
\ No newline at end of file
diff --git a/test/samples/global-style/expected.json b/test/samples/global-style/expected.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/test/samples/global-style/expected.json
@@ -0,0 +1 @@
+[]