From d63a5b23b1725bd53504f952eca1cd887b685773 Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Fri, 9 Jun 2017 19:59:48 -0400
Subject: [PATCH] Handled uiOpenTypeFeatures NULL equality. This only added
 more TODOs elsewhere :|

---
 darwin/attrstr.m     | 8 +-------
 darwin/opentype.m    | 4 ++++
 ui_attrstr.h         | 7 ++-----
 unix/attrstr.c       | 2 +-
 unix/opentype.c      | 5 +++++
 windows/attrstr.cpp  | 1 +
 windows/opentype.cpp | 4 ++++
 7 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/darwin/attrstr.m b/darwin/attrstr.m
index c3b8b0b3..4d166fb0 100644
--- a/darwin/attrstr.m
+++ b/darwin/attrstr.m
@@ -113,13 +113,7 @@ struct foreachParams {
 		return NO;
 	if (self.stretch != b.stretch)
 		return NO;
-	// TODO make this part of uiOpenTypeFeaturesEqual() on all platforms
-	if (self.features == NULL && b.features == NULL)
-		return YES;
-	if (self.features != NULL && b.features == NULL)
-		return NO;
-	if (self.features == NULL && b.features != NULL)
-		return NO;
+	// this also handles NULL cases
 	if (!uiOpenTypeFeaturesEqual(self.features, b.features))
 		return NO;
 	return YES;
diff --git a/darwin/opentype.m b/darwin/opentype.m
index 24f35f63..46bdaf19 100644
--- a/darwin/opentype.m
+++ b/darwin/opentype.m
@@ -87,6 +87,10 @@ void uiOpenTypeFeaturesForEach(const uiOpenTypeFeatures *otf, uiOpenTypeFeatures
 
 int uiOpenTypeFeaturesEqual(const uiOpenTypeFeatures *a, const uiOpenTypeFeatures *b)
 {
+	if (a == NULL && b == NULL)
+		return 1;
+	if (a == NULL || b == NULL)
+		return 0;
 	return [a->tags isEqualToDictionary:b->tags];
 }
 
diff --git a/ui_attrstr.h b/ui_attrstr.h
index c7ab225c..b39b39a2 100644
--- a/ui_attrstr.h
+++ b/ui_attrstr.h
@@ -142,11 +142,8 @@ _UI_EXTERN int uiOpenTypeFeaturesGet(uiOpenTypeFeatures *otf, char a, char b, ch
 _UI_EXTERN void uiOpenTypeFeaturesForEach(const uiOpenTypeFeatures *otf, uiOpenTypeFeaturesForEachFunc f, void *data);
 
 // uiOpenTypeFeaturesEqual() returns nonzero if a is equal to b.
-// a is defined as equal to b if and only if both
-// - contain the same tags, without any extras or missing tags
-// 	either way, and
-// - have each tag have the same values
-// TODO what if either or both are NULL?
+// a is defined as equal to b if and only if both have exactly the same
+// tags with exactly the same values, or if both are NULL.
 _UI_EXTERN int uiOpenTypeFeaturesEqual(const uiOpenTypeFeatures *a, const uiOpenTypeFeatures *b);
 
 typedef struct uiAttributeSpec uiAttributeSpec;
diff --git a/unix/attrstr.c b/unix/attrstr.c
index 7dc83a6e..4d384daf 100644
--- a/unix/attrstr.c
+++ b/unix/attrstr.c
@@ -154,7 +154,7 @@ static uiForEach processAttribute(uiAttributedString *s, uiAttributeSpec *spec,
 		}
 		break;
 	case uiAttributeFeatures:
-		// TODO handle NULLs properly on all platforms
+		// TODO make sure NULLs are handled properly on all platforms in this part of the code
 		featurestr = otfToPangoCSSString(spec->Features);
 		addattr(p, start, end,
 			FUTURE_pango_attr_font_features_new(featurestr));
diff --git a/unix/opentype.c b/unix/opentype.c
index 9b90d0ba..79b1d93a 100644
--- a/unix/opentype.c
+++ b/unix/opentype.c
@@ -133,6 +133,11 @@ int uiOpenTypeFeaturesEqual(const uiOpenTypeFeatures *a, const uiOpenTypeFeature
 	guint i;
 	int equal = 0;
 
+	if (a == NULL && b == NULL)
+		return 1;
+	if (a == NULL || b == NULL)
+		return 0;
+
 	ak = copySortedKeys(a->tags);
 	bk = copySortedKeys(b->tags);
 
diff --git a/windows/attrstr.cpp b/windows/attrstr.cpp
index 7bcd5e53..9dceaea6 100644
--- a/windows/attrstr.cpp
+++ b/windows/attrstr.cpp
@@ -174,6 +174,7 @@ static uiForEach processAttribute(uiAttributedString *s, uiAttributeSpec *spec,
 		}
 		break;
 	case uiAttributeFeatures:
+		// TODO make sure this behaves properly if spec->Features is NULL
 		dt = otfToDirectWrite(spec->Features);
 		hr = p->layout->SetTypography(dt, range);
 		if (hr != S_OK)
diff --git a/windows/opentype.cpp b/windows/opentype.cpp
index 21833e2c..89b5913c 100644
--- a/windows/opentype.cpp
+++ b/windows/opentype.cpp
@@ -79,6 +79,10 @@ void uiOpenTypeFeaturesForEach(const uiOpenTypeFeatures *otf, uiOpenTypeFeatures
 
 int uiOpenTypeFeaturesEqual(const uiOpenTypeFeatures *a, const uiOpenTypeFeatures *b)
 {
+	if (a == NULL && b == NULL)
+		return 1;
+	if (a == NULL || b == NULL)
+		return 0;
 	// TODO make sure this is correct
 	return *(a->tags) == *(b->tags);
 }