From fd9f6cea6a603954619ef880ce6d2f5c63daf4b9 Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Sat, 14 May 2016 22:09:02 -0400
Subject: [PATCH] Allowed uiGroups and uiTabs to have no and NULL controls with
 defined behavior on OS X. Actually added the test code this time.

---
 darwin/tab.m  | 44 +++++++++++++++++++++++++-----------------
 test/page11.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+), 17 deletions(-)
 create mode 100644 test/page11.c

diff --git a/darwin/tab.m b/darwin/tab.m
index 0e7a0d19..a98bf0fd 100644
--- a/darwin/tab.m
+++ b/darwin/tab.m
@@ -58,6 +58,7 @@ struct uiTab {
 {
 	[self removeChildConstraints];
 	if (self.c == NULL)
+		// TODO make sure we need the margins
 		return;
 	singleChildConstraintsEstablish(&(self->constraints),
 		self->view, [self childView],
@@ -97,9 +98,11 @@ static void uiTabDestroy(uiControl *c)
 	// then destroy all the children
 	for (page in t->pages) {
 		[page removeChildConstraints];
-		uiControlSetParent(page.c, NULL);
-		uiDarwinControlSetSuperview(uiDarwinControl(page.c), nil);
-		uiControlDestroy(page.c);
+		if (page.c != NULL) {
+			uiControlSetParent(page.c, NULL);
+			uiDarwinControlSetSuperview(uiDarwinControl(page.c), nil);
+			uiControlDestroy(page.c);
+		}
 	}
 	// and finally destroy ourselves
 	[t->pages release];
@@ -187,23 +190,26 @@ void uiTabInsertAt(uiTab *t, const char *name, uintmax_t n, uiControl *child)
 	NSTabViewItem *i;
 	NSObject *pageID;
 
-	uiControlSetParent(child, uiControl(t));
-
 	view = [[NSView alloc] initWithFrame:NSZeroRect];
-	// TODO if we turn off the autoresizing mask, nothing shows up; didn't this get documented somewhere?
-	uiDarwinControlSetSuperview(uiDarwinControl(child), view);
-	uiDarwinControlSyncEnableState(uiDarwinControl(child), uiControlEnabledToUser(uiControl(t)));
+	// don't turn off the autoresizing mask on view; if we do, nothing shows up
+	if (child != NULL) {
+		uiControlSetParent(child, uiControl(t));
+		uiDarwinControlSetSuperview(uiDarwinControl(child), view);
+		uiDarwinControlSyncEnableState(uiDarwinControl(child), uiControlEnabledToUser(uiControl(t)));
+	}
 
 	// the documentation says these can be nil but the headers say these must not be; let's be safe and make them non-nil anyway
 	pageID = [NSObject new];
 	page = [[tabPage alloc] initWithView:view pageID:pageID];
 	page.c = child;
 
-	// don't hug, just in case we're a stretchy tab
-	page.oldHorzHuggingPri = uiDarwinControlHuggingPriority(uiDarwinControl(page.c), NSLayoutConstraintOrientationHorizontal);
-	page.oldVertHuggingPri = uiDarwinControlHuggingPriority(uiDarwinControl(page.c), NSLayoutConstraintOrientationVertical);
-	uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), NSLayoutPriorityDefaultLow, NSLayoutConstraintOrientationHorizontal);
-	uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), NSLayoutPriorityDefaultLow, NSLayoutConstraintOrientationVertical);
+	if (page.c != NULL) {
+		// don't hug, just in case we're a stretchy tab
+		page.oldHorzHuggingPri = uiDarwinControlHuggingPriority(uiDarwinControl(page.c), NSLayoutConstraintOrientationHorizontal);
+		page.oldVertHuggingPri = uiDarwinControlHuggingPriority(uiDarwinControl(page.c), NSLayoutConstraintOrientationVertical);
+		uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), NSLayoutPriorityDefaultLow, NSLayoutConstraintOrientationHorizontal);
+		uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), NSLayoutPriorityDefaultLow, NSLayoutConstraintOrientationVertical);
+	}
 
 	[t->pages insertObject:page atIndex:n];
 	[page release];			// no need for initial reference
@@ -228,15 +234,19 @@ void uiTabDelete(uiTab *t, uintmax_t n)
 
 	page = (tabPage *) [t->pages objectAtIndex:n];
 
-	uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), page.oldHorzHuggingPri, NSLayoutConstraintOrientationHorizontal);
-	uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), page.oldVertHuggingPri, NSLayoutConstraintOrientationVertical);
+	if (page.c != NULL) {
+		uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), page.oldHorzHuggingPri, NSLayoutConstraintOrientationHorizontal);
+		uiDarwinControlSetHuggingPriority(uiDarwinControl(page.c), page.oldVertHuggingPri, NSLayoutConstraintOrientationVertical);
+	}
 
 	child = page.c;
 	[page removeChildConstraints];
 	[t->pages removeObjectAtIndex:n];
 
-	uiControlSetParent(child, NULL);
-	uiDarwinControlSetSuperview(uiDarwinControl(child), nil);
+	if (child != NULL) {
+		uiControlSetParent(child, NULL);
+		uiDarwinControlSetSuperview(uiDarwinControl(child), nil);
+	}
 
 	i = [t->tabview tabViewItemAtIndex:n];
 	[t->tabview removeTabViewItem:i];
diff --git a/test/page11.c b/test/page11.c
new file mode 100644
index 00000000..cbe3d6cd
--- /dev/null
+++ b/test/page11.c
@@ -0,0 +1,53 @@
+// 14 may 2016
+#include "test.h"
+
+// TODO add a test for childless windows
+
+static uiGroup *newg(const char *n, int s)
+{
+	uiGroup *g;
+
+	g = uiNewGroup(n);
+	if (s)
+		uiGroupSetChild(g, NULL);
+	return g;
+}
+
+static uiTab *newt(int tt)
+{
+	uiTab *t;
+
+	t = uiNewTab();
+	if (tt)
+		uiTabAppend(t, "Test", NULL);
+	return t;
+}
+
+uiBox *makePage11(void)
+{
+	uiBox *page11;
+	uiBox *ns;
+	uiBox *s;
+
+	page11 = newHorizontalBox();
+
+	ns = newVerticalBox();
+	uiBoxAppend(ns, uiControl(newg("", 0)), 0);
+	uiBoxAppend(ns, uiControl(newg("", 1)), 0);
+	uiBoxAppend(ns, uiControl(newg("Group", 0)), 0);
+	uiBoxAppend(ns, uiControl(newg("Group", 1)), 0);
+	uiBoxAppend(ns, uiControl(newt(0)), 0);
+	uiBoxAppend(ns, uiControl(newt(1)), 0);
+	uiBoxAppend(page11, uiControl(ns), 1);
+
+	s = newVerticalBox();
+	uiBoxAppend(s, uiControl(newg("", 0)), 1);
+	uiBoxAppend(s, uiControl(newg("", 1)), 1);
+	uiBoxAppend(s, uiControl(newg("Group", 0)), 1);
+	uiBoxAppend(s, uiControl(newg("Group", 1)), 1);
+	uiBoxAppend(s, uiControl(newt(0)), 1);
+	uiBoxAppend(s, uiControl(newt(1)), 1);
+	uiBoxAppend(page11, uiControl(s), 1);
+
+	return page11;
+}