Stop hiding the column number of ESLint errors (#6980)

Author: justingrant

packages/react-dev-utils/formatWebpackMessages.js

@@ -41,9 +41,6 @@ function formatMessage(message) {
     /SyntaxError\s+\((\d+):(\d+)\)\s*(.+?)\n/g,
     `${friendlySyntaxErrorLabel} $3 ($1:$2)\n`
   );
-  // Remove columns from ESLint formatter output (we added these for more
-  // accurate syntax errors)
-  message = message.replace(/Line (\d+):\d+:/g, 'Line $1:');
   // Clean up export errors
   message = message.replace(
     /^.*export '(.+?)' was not found in '(.+?)'.*$/gm,

test/fixtures/webpack-message-formatting/__snapshots__/index.test.js.snap

@@ -62,7 +62,7 @@ Object {
 Failed to compile.
 
 ./src/App.js
-  Line 4:  'b' is not defined  no-undef
+  Line 4:13:  'b' is not defined  no-undef
 
 Search for the keywords to learn more about each error.
 
@@ -79,7 +79,7 @@ Object {
 Compiled with warnings.
 
 ./src/App.js
-  Line 3:  'foo' is defined but never used  no-unused-vars
+  Line 3:10:  'foo' is defined but never used  no-unused-vars
 
 Search for the keywords to learn more about each warning.
 To ignore, add // eslint-disable-next-line to the line before.