From 25b765c123ee4779d223b10adbea8db5c472d5a0 Mon Sep 17 00:00:00 2001
From: Fenzland <fenzland@163.com>
Date: Sat, 2 May 2020 01:03:54 +0800
Subject: [PATCH] fix misaligned error reporting on tab char (#5032)

---
 cli/fmt_errors.rs                  | 6 +++++-
 cli/tests/error_025_tab_indent     | 9 +++++++++
 cli/tests/error_025_tab_indent.out | 6 ++++++
 cli/tests/integration_tests.rs     | 7 +++++++
 core/js_errors.rs                  | 5 ++++-
 5 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 cli/tests/error_025_tab_indent
 create mode 100644 cli/tests/error_025_tab_indent.out

diff --git a/cli/fmt_errors.rs b/cli/fmt_errors.rs
index d2c69819f4..e0fc614592 100644
--- a/cli/fmt_errors.rs
+++ b/cli/fmt_errors.rs
@@ -74,7 +74,11 @@ fn format_maybe_source_line(
     '~'
   };
   for _i in 0..start_column {
-    s.push(' ');
+    if source_line.chars().nth(_i as usize).unwrap() == '\t' {
+      s.push('\t');
+    } else {
+      s.push(' ');
+    }
   }
   for _i in 0..(end_column - start_column) {
     s.push(underline_char);
diff --git a/cli/tests/error_025_tab_indent b/cli/tests/error_025_tab_indent
new file mode 100644
index 0000000000..35a25bceae
--- /dev/null
+++ b/cli/tests/error_025_tab_indent
@@ -0,0 +1,9 @@
+function foo() {
+	throw Error("bad");
+}
+
+function bar() {
+	foo();
+}
+
+bar();
diff --git a/cli/tests/error_025_tab_indent.out b/cli/tests/error_025_tab_indent.out
new file mode 100644
index 0000000000..7b339c48fe
--- /dev/null
+++ b/cli/tests/error_025_tab_indent.out
@@ -0,0 +1,6 @@
+[WILDCARD]error: Uncaught Error: bad
+	throw Error("bad");
+	      ^
+    at foo ([WILDCARD]tests/error_025_tab_indent:2:8)
+    at bar ([WILDCARD]tests/error_025_tab_indent:6:2)
+    at [WILDCARD]tests/error_025_tab_indent:9:1
diff --git a/cli/tests/integration_tests.rs b/cli/tests/integration_tests.rs
index fb2d7e73b0..66df5a70ff 100644
--- a/cli/tests/integration_tests.rs
+++ b/cli/tests/integration_tests.rs
@@ -1429,6 +1429,13 @@ itest!(error_024_stack_promise_all {
   exit_code: 1,
 });
 
+itest!(error_025_tab_indent {
+  args: "error_025_tab_indent",
+  output: "error_025_tab_indent.out",
+  check_stderr: true,
+  exit_code: 1,
+});
+
 itest!(error_syntax {
   args: "run --reload error_syntax.js",
   check_stderr: true,
diff --git a/core/js_errors.rs b/core/js_errors.rs
index 0e3f8cb914..dfad7238ec 100644
--- a/core/js_errors.rs
+++ b/core/js_errors.rs
@@ -274,11 +274,14 @@ impl fmt::Display for JSError {
         write!(f, "{}", source_loc)?;
       }
       if self.source_line.is_some() {
-        write!(f, "\n{}\n", self.source_line.as_ref().unwrap())?;
+        let source_line = self.source_line.as_ref().unwrap();
+        write!(f, "\n{}\n", source_line)?;
         let mut s = String::new();
         for i in 0..self.end_column.unwrap() {
           if i >= self.start_column.unwrap() {
             s.push('^');
+          } else if source_line.chars().nth(i as usize).unwrap() == '\t' {
+            s.push('\t');
           } else {
             s.push(' ');
           }