add component state, top-level await support (#26)

1 files changed, 27 insertions, 0 deletions

diff --git a/src/parser/utils/get_code_frame.ts b/src/parser/utils/get_code_frame.ts
new file mode 100644
index 000000000..a0c296672
--- /dev/null
+++ b/src/parser/utils/get_code_frame.ts
@@ -0,0 +1,27 @@
+function tabs_to_spaces(str: string) {
+  return str.replace(/^\t+/, (match) => match.split('\t').join('  '));
+}
+
+export default function get_code_frame(source: string, line: number, column: number) {
+  const lines = source.split('\n');
+
+  const frame_start = Math.max(0, line - 2);
+  const frame_end = Math.min(line + 3, lines.length);
+
+  const digits = String(frame_end + 1).length;
+
+  return lines
+    .slice(frame_start, frame_end)
+    .map((str, i) => {
+      const isErrorLine = frame_start + i === line;
+      const line_num = String(i + frame_start + 1).padStart(digits, ' ');
+
+      if (isErrorLine) {
+        const indicator = ' '.repeat(digits + 2 + tabs_to_spaces(str.slice(0, column)).length) + '^';
+        return `${line_num}: ${tabs_to_spaces(str)}\n${indicator}`;
+      }
+
+      return `${line_num}: ${tabs_to_spaces(str)}`;
+    })
+    .join('\n');
+}