Add support for string literals to TypeScriptLexer.

This introduces support for string literals to the TypeScript lexer. The rules
are consistent with those in JavascriptLexer, helping to ensure the same
behavior and capabilities between the two.

1 files changed, 18 insertions, 1 deletions

diff --git a/pygments/lexers/javascript.py b/pygments/lexers/javascript.py
index 4b47b15a..b379fc02 100644
--- a/pygments/lexers/javascript.py
+++ b/pygments/lexers/javascript.py
@@ -511,9 +511,26 @@ class TypeScriptLexer(RegexLexer):
             (r'[0-9]+', Number.Integer),
             (r'"(\\\\|\\"|[^"])*"', String.Double),
             (r"'(\\\\|\\'|[^'])*'", String.Single),
+            (r'`', String.Backtick, 'interp'),
             # Match stuff like: Decorators
             (r'@\w+', Keyword.Declaration),
-        ]
+        ],
+
+        # The 'interp*' rules match those in JavascriptLexer. Changes made
+        # there should be reflected here as well.
+        'interp': [
+            (r'`', String.Backtick, '#pop'),
+            (r'\\\\', String.Backtick),
+            (r'\\`', String.Backtick),
+            (r'\$\{', String.Interpol, 'interp-inside'),
+            (r'\$', String.Backtick),
+            (r'[^`\\$]+', String.Backtick),
+        ],
+        'interp-inside': [
+            # TODO: should this include single-line comments and allow nesting strings?
+            (r'\}', String.Interpol, '#pop'),
+            include('root'),
+        ],
     }