Merge pull request #512 from simoncozens/fix-506

Maintain order of features when writing
googlefonts · Jul 16, 2021 · 232c316 · 232c316
2 parents dcff218 + 63886ad
commit 232c316
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Showing 2 changed files with 37 additions and 20 deletions.
diff --git a/Lib/ufo2ft/featureWriters/baseFeatureWriter.py b/Lib/ufo2ft/featureWriters/baseFeatureWriter.py
@@ -157,12 +157,12 @@ def _insert(
         """
 
         statements = feaFile.statements
+        inserted = {}
 
-        # Collect insert markers in blocks
+        # First handle those with a known location, i.e. insert markers
         insertComments = self.context.insertComments
-
         indices = []
-        for feature in features:
+        for ix, feature in enumerate(features):
             if insertComments and feature.name in insertComments:
                 block, comment = insertComments[feature.name]
                 markerIndex = block.statements.index(comment)
@@ -207,8 +207,25 @@ def _insert(
                         f"{block.name} cannot be inserted. This is not supported."
                     )
 
-            else:
-                index = len(statements)
+                statements.insert(index, feature)
+                indices.append(index)
+                inserted[id(feature)] = True
+
+                # Now walk feature list backwards and insert any dependent features
+                for i in range(ix - 1, -1, -1):
+                    if id(features[i]) in inserted:
+                        break
+                    # Insert this before the current one i.e. at same array index
+                    statements.insert(index, features[i])
+                    # All the indices recorded previously have now shifted up by one
+                    indices = [index] + [j + 1 for j in indices]
+                    inserted[id(features[i])] = True
+
+        # Finally, deal with any remaining features
+        for feature in features:
+            if id(feature) in inserted:
+                continue
+            index = len(statements)
             statements.insert(index, feature)
             indices.append(index)
 

diff --git a/tests/featureWriters/markFeatureWriter_test.py b/tests/featureWriters/markFeatureWriter_test.py
@@ -573,6 +573,21 @@ def test_defs_and_lookups_first(self, testufo):
             markClass acutecomb <anchor 100 200> @MC_top;
             markClass tildecomb <anchor 100 200> @MC_top;
 
+            feature mark {
+                lookup mark2base {
+                    pos base a
+                        <anchor 100 200> mark @MC_top;
+                } mark2base;
+
+                lookup mark2liga {
+                    pos ligature f_i
+                            <anchor 100 500> mark @MC_top
+                        ligComponent
+                            <anchor 600 500> mark @MC_top;
+                } mark2liga;
+
+            } mark;
+
             feature mkmk {
                 lookup mark2mark_top {
                     @MFS_mark2mark_top = [acutecomb tildecomb];
@@ -591,21 +606,6 @@ def test_defs_and_lookups_first(self, testufo):
                 } move_acutecomb;
 
             } mkmk;
-
-            feature mark {
-                lookup mark2base {
-                    pos base a
-                        <anchor 100 200> mark @MC_top;
-                } mark2base;
-
-                lookup mark2liga {
-                    pos ligature f_i
-                            <anchor 100 500> mark @MC_top
-                        ligComponent
-                            <anchor 600 500> mark @MC_top;
-                } mark2liga;
-
-            } mark;
             """
         )