Reworked the relative/absolute import system.

Now, it works more like HTML URL resolution, where any URL is relative
unless it starts with a /.

7 files changed, 85 insertions, 53 deletions

diff --git a/README.rst b/README.rst
index d8c9639..6c8391d 100644
--- a/README.rst
+++ b/README.rst
@@ -41,9 +41,7 @@ You can render SCSS from a file like this::
     compiler.compile(scss_file='css/styles.scss')
 
 The file needs to be able to be located by staticfiles finders in order to be
-used.  All imports are relative to the ``STATIC_ROOT``, but you can also have
-relative imports from a file.  If you prefix an import with ``./``, you can
-import a sibling file without having to write out the whole import path.
+used.
 
 
 .. class:: django_pyscss.scss.DjangoScss
diff --git a/django_pyscss/compressor.py b/django_pyscss/compressor.py
index ab13f77..6ec9e31 100644
--- a/django_pyscss/compressor.py
+++ b/django_pyscss/compressor.py
@@ -3,6 +3,7 @@ from __future__ import absolute_import
 import os
 
 from compressor.filters import FilterBase
+from compressor.conf import settings
 
 from django_pyscss.scss import DjangoScss, config
 
@@ -14,8 +15,18 @@ class DjangoScssFilter(FilterBase):
         # It looks like there is a bug in django-compressor because it expects
         # us to accept attrs.
         super(DjangoScssFilter, self).__init__(content, filter_type, filename)
+        try:
+            # this is a link tag which means there is an SCSS file being
+            # referenced.
+            href = attrs['href']
+        except KeyError:
+            # this is a style tag which means this is inline SCSS.
+            self.relative_to = None
+        else:
+            self.relative_to = os.path.dirname(href.replace(settings.STATIC_URL, ''))
 
     def input(self, **kwargs):
         if not os.path.exists(config.ASSETS_ROOT):
             os.makedirs(config.ASSETS_ROOT)
-        return self.compiler.compile(self.content)
+        return self.compiler.compile(scss_string=self.content,
+                                     relative_to=self.relative_to)
diff --git a/django_pyscss/scss.py b/django_pyscss/scss.py
index 03e6c57..3423b2c 100644
--- a/django_pyscss/scss.py
+++ b/django_pyscss/scss.py
@@ -4,7 +4,6 @@ import os
 
 from django.contrib.staticfiles.storage import staticfiles_storage
 from django.conf import settings
-from django.core.exceptions import SuspiciousFileOperation
 
 from scss import (
     Scss, dequote, log, SourceFile, SassRule, config,
@@ -48,26 +47,39 @@ class DjangoScss(Scss):
         else:
             return self.get_file_from_storage(filename)
 
-    def _find_source_file(self, name):
-        file_and_storage = self.get_file_and_storage(name)
-        if file_and_storage is None:
-            return None
-        else:
-            full_filename, storage = file_and_storage
-        if name not in self.source_files:
-            with storage.open(full_filename) as f:
-                source = f.read()
-
-            source_file = SourceFile(
-                full_filename,
-                source,
-            )
-            # SourceFile.__init__ calls os.path.realpath on this, we don't want
-            # that.
-            source_file.parent_dir = os.path.dirname(name)
-            self.source_files.append(source_file)
-            self.source_file_index[full_filename] = source_file
-        return self.source_file_index[full_filename]
+    def get_possible_import_paths(self, filename, relative_to=None):
+        """
+        Returns an iterable of possible filenames for an import.
+
+        relative_to is None in the case that the SCSS is being rendered from a
+        string or if it is the first file.
+        """
+        if filename.startswith('/'):  # absolute import
+            filename = filename[1:]
+        elif relative_to:  # relative import
+            filename = os.path.join(relative_to, filename)
+
+        return [filename]
+
+    def _find_source_file(self, filename, relative_to=None):
+        for name in self.get_possible_import_paths(filename, relative_to):
+            file_and_storage = self.get_file_and_storage(name)
+            if file_and_storage:
+                full_filename, storage = file_and_storage
+                if name not in self.source_files:
+                    with storage.open(full_filename) as f:
+                        source = f.read()
+
+                    source_file = SourceFile(
+                        full_filename,
+                        source,
+                    )
+                    # SourceFile.__init__ calls os.path.realpath on this, we don't want
+                    # that, we want them to remain relative.
+                    source_file.parent_dir = os.path.dirname(name)
+                    self.source_files.append(source_file)
+                    self.source_file_index[full_filename] = source_file
+                return self.source_file_index[full_filename]
 
     def _do_import(self, rule, scope, block):
         """
@@ -83,10 +95,8 @@ class DjangoScss(Scss):
         for name in names:
             name = dequote(name.strip())
 
-            if name.startswith('./'):
-                name = rule.source_file.parent_dir + name[1:]
-
-            source_file = self._find_source_file(name)
+            relative_to = rule.source_file.parent_dir
+            source_file = self._find_source_file(name, relative_to)
 
             if source_file is None:
                 i_codestr = self._do_magic_import(rule, scope, block)
@@ -121,10 +131,12 @@ class DjangoScss(Scss):
             rule.namespace.add_import(import_key, rule.import_key, rule.file_and_line)
             self.manage_children(_rule, scope)
 
-    def Compilation(self, scss_string=None, scss_file=None, super_selector=None, filename=None, is_sass=None, line_numbers=True):
+    def Compilation(self, scss_string=None, scss_file=None, super_selector=None,
+                    filename=None, is_sass=None, line_numbers=True,
+                    relative_to=None):
         """
         Overwritten to call _find_source_file instead of
-        SourceFile.from_filename.
+        SourceFile.from_filename.  Also added the relative_to option.
         """
         if super_selector:
             self.super_selector = super_selector + ' '
@@ -133,6 +145,9 @@ class DjangoScss(Scss):
         source_file = None
         if scss_string is not None:
             source_file = SourceFile.from_string(scss_string, filename, is_sass, line_numbers)
+            # Set the parent_dir to be something meaningful instead of the
+            # current working directory, which is never correct for DjangoScss.
+            source_file.parent_dir = relative_to
         elif scss_file is not None:
             # Call _find_source_file instead of SourceFile.from_filename
             source_file = self._find_source_file(scss_file)
diff --git a/testproject/testapp2/static/css/app2.scss b/testproject/testapp2/static/css/app2.scss
index d19b910..a096082 100644
--- a/testproject/testapp2/static/css/app2.scss
+++ b/testproject/testapp2/static/css/app2.scss
@@ -1,2 +1,2 @@
-@import "css/foo.scss";
-@import "css/app1.scss";
+@import "foo.scss";
+@import "app1.scss";
diff --git a/testproject/testproject/static/css/bar.scss b/testproject/testproject/static/css/bar.scss
index 448776a..08819e4 100644
--- a/testproject/testproject/static/css/bar.scss
+++ b/testproject/testproject/static/css/bar.scss
@@ -1 +1 @@
-@import "./foo.scss";
+@import "foo.scss";
diff --git a/tests/test_compressor.py b/tests/test_compressor.py
index 4f8f64e..4ff6630 100644
--- a/tests/test_compressor.py
+++ b/tests/test_compressor.py
@@ -9,8 +9,23 @@ APP2_LINK_TAG = """
 {% endcompress %}
 """
 
+IMPORT_APP2_STYLE_TAG = """
+{% load staticfiles compress %}
+{% compress css %}
+<style type="text/x-scss">
+@import "css/app2.scss";
+</style>
+{% endcompress %}
+"""
+
 
 class CompressorTest(TestCase):
     def test_compressor_can_compile_scss(self):
         actual = Template(APP2_LINK_TAG).render(Context())
+        # 4b368862ec8c is the cache key that compressor gives to the compiled
+        # version of app2.scss.
+        self.assertIn('4b368862ec8c.css', actual)
+
+    def test_compressor_can_compile_scss_from_style_tag(self):
+        actual = Template(IMPORT_APP2_STYLE_TAG).render(Context())
         self.assertIn('4b368862ec8c.css', actual)
diff --git a/tests/test_scss.py b/tests/test_scss.py
index 3178f6b..d538068 100644
--- a/tests/test_scss.py
+++ b/tests/test_scss.py
@@ -9,26 +9,12 @@ from django_pyscss.scss import DjangoScss
 from tests.utils import clean_css, CollectStaticTestCase
 
 
-IMPORT_FOO = """
-@import "css/foo.scss";
-"""
-
 with open(os.path.join(settings.BASE_DIR, 'testproject', 'static', 'css', 'foo.scss')) as f:
     FOO_CONTENTS = f.read()
 
-
-IMPORT_APP1 = """
-@import "css/app1.scss";
-"""
-
 with open(os.path.join(settings.BASE_DIR, 'testapp1', 'static', 'css', 'app1.scss')) as f:
     APP1_CONTENTS = f.read()
 
-
-IMPORT_APP2 = """
-@import "css/app2.scss";
-"""
-
 APP2_CONTENTS = FOO_CONTENTS + APP1_CONTENTS
 
 
@@ -43,20 +29,27 @@ class CompilerTestMixin(object):
 
 class ImportTestMixin(CompilerTestMixin):
     def test_import_from_staticfiles_dirs(self):
-        actual = self.compiler.compile(scss_string=IMPORT_FOO)
+        actual = self.compiler.compile(scss_string='@import "/css/foo.scss";')
+        self.assertEqual(clean_css(actual), clean_css(FOO_CONTENTS))
+
+    def test_import_from_staticfiles_dirs_relative(self):
+        actual = self.compiler.compile(scss_string='@import "css/foo.scss";')
         self.assertEqual(clean_css(actual), clean_css(FOO_CONTENTS))
 
     def test_import_from_app(self):
-        actual = self.compiler.compile(scss_string=IMPORT_APP1)
+        actual = self.compiler.compile(scss_string='@import "/css/app1.scss";')
+        self.assertEqual(clean_css(actual), clean_css(APP1_CONTENTS))
+
+    def test_import_from_app_relative(self):
+        actual = self.compiler.compile(scss_string='@import "css/app1.scss";')
         self.assertEqual(clean_css(actual), clean_css(APP1_CONTENTS))
 
     def test_imports_within_file(self):
-        actual = self.compiler.compile(scss_string=IMPORT_APP2)
+        actual = self.compiler.compile(scss_string='@import "/css/app2.scss";')
         self.assertEqual(clean_css(actual), clean_css(APP2_CONTENTS))
 
     def test_relative_import(self):
-        bar_scss = 'css/bar.scss'
-        actual = self.compiler.compile(scss_file=bar_scss)
+        actual = self.compiler.compile(scss_file='/css/bar.scss')
         self.assertEqual(clean_css(actual), clean_css(FOO_CONTENTS))
 
     def test_bad_import(self):