Support source map generation with -g option

Author: vsalvino

README.md

@@ -61,10 +61,11 @@ In `app2.scss` you could reference app1's and app2's `_colors.scss` import as so
 ```
 
 Then to compile `app2.scss` and put it in the `css` directory,
-run the following management command:
+run the following management command (the `-g` will build a source map, which
+is helpful for debugging CSS):
 
 ```
-python manage.py sass app2/static/app2/scss/app2.scss app2/static/app2/css/app2.css
+python manage.py sass app2/static/app2/scss/app2.scss app2/static/app2/css/app2.css -g
 ```
 
 Or, you can compile the entire `scss` directory into
@@ -141,9 +142,7 @@ Limitations
 
 * Only files ending in `.scss` are supported for now.
 
-* Source map generation is not supported yet.
-
-* Only supports `-t` and `-p` options similar to `pysassc`. Ideally `django-sass` will
+* Only supports `-g`, `-p`, and `-t` options similar to `pysassc`. Ideally `django-sass` will
   be as similar as possible to the `pysassc` command line interface.
 
 Feel free to file an issue or make a pull request to improve any of these limitations. 🐱‍💻
@@ -173,6 +172,9 @@ and Linux), and of course Django (any version).
 Changelog
 ---------
 
+#### 0.2.0
+* New feature: `-g` option to build a source map (when input is a file, not a directory).
+
 #### 0.1.2
 * Fix: Write compiled CSS files as UTF-8.
 * Change: Default `-p` precision from 5 to 8 for better support building Bootstrap CSS.

django_sass/__init__.py

@@ -1 +1 @@
-__version__ = "0.1.2"
+__version__ = "0.2.0"

django_sass/management/commands/sass.py

@@ -22,6 +22,12 @@ def add_arguments(self, parser):
             nargs="+",
             help="A file or directory in which to output transpiled css",
         )
+        parser.add_argument(
+            "-g",
+            dest="g",
+            action="store_true",
+            help="Build a sourcemap. Only applicable if input is a file, not a directory.",
+        )
         parser.add_argument(
             "-t",
             type=str,
@@ -49,7 +55,18 @@ def compile_sass(self, outfile, **kwargs):
         # sass.compile() will return None of used with dirname.
         # If used with filename, it will return a string of file contents.
         if rval and outfile:
-            # Write the outputted css to file
+            # If we got a css and sourcemap tuple, write the sourcemap.
+            if isinstance(rval, tuple):
+                map_outfile = outfile + ".map"
+                outfile_dir = os.path.dirname(map_outfile)
+                if not os.path.exists(outfile_dir):
+                    os.makedirs(outfile_dir, exist_ok=True)
+                file = open(map_outfile, "w", encoding="utf8")
+                file.write(rval[1])
+                file.close()
+                rval = rval[0]
+
+            # Write the outputted css to file.
             outfile_dir = os.path.dirname(outfile)
             if not os.path.exists(outfile_dir):
                 os.makedirs(outfile_dir, exist_ok=True)
@@ -79,7 +96,7 @@ def handle(self, *args, **options):
             sassargs.update({"include_paths": found_paths})
 
         if os.path.isdir(inpath):
-            # assume outpath is also a dir, or make it
+            # Assume outpath is also a dir, or make it.
             if not os.path.exists(outpath):
                 os.makedirs(outpath)
             if os.path.isdir(outpath):
@@ -95,8 +112,10 @@ def handle(self, *args, **options):
                 )
             else:
                 outfile = outpath
+            if options["g"]:
+                sassargs.update({"source_map_filename": outfile + ".map"})
 
-         # Watch files for changes if specified
+         # Watch files for changes if specified.
         if options["watch"]:
             try:
                 self.stdout.write("Watching...")