From 7f524b2a04a0cbb4624d1ddc1c29eae292b71b06 Mon Sep 17 00:00:00 2001
From: Dongjin Suh <rhanwith@linecorp.com>
Date: Mon, 19 Dec 2016 19:02:10 +0900
Subject: [PATCH] Add mas_removeExistingConstraints method.

---
 Masonry/MASConstraintMaker.m         | 5 +----
 Masonry/NSArray+MASAdditions.h       | 5 +++++
 Masonry/NSArray+MASAdditions.m       | 7 +++++++
 Masonry/View+MASAdditions.h          | 5 +++++
 Masonry/View+MASAdditions.m          | 8 ++++++++
 Masonry/View+MASShorthandAdditions.h | 4 ++++
 6 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/Masonry/MASConstraintMaker.m b/Masonry/MASConstraintMaker.m
index 55f90bcf..ee4874ac 100644
--- a/Masonry/MASConstraintMaker.m
+++ b/Masonry/MASConstraintMaker.m
@@ -34,10 +34,7 @@ - (id)initWithView:(MAS_VIEW *)view {
 
 - (NSArray *)install {
     if (self.removeExisting) {
-        NSArray *installedConstraints = [MASViewConstraint installedConstraintsForView:self.view];
-        for (MASConstraint *constraint in installedConstraints) {
-            [constraint uninstall];
-        }
+        [self.view mas_removeExistingConstraints];
     }
     NSArray *constraints = self.constraints.copy;
     for (MASConstraint *constraint in constraints) {
diff --git a/Masonry/NSArray+MASAdditions.h b/Masonry/NSArray+MASAdditions.h
index 587618d9..9eb2e1c9 100644
--- a/Masonry/NSArray+MASAdditions.h
+++ b/Masonry/NSArray+MASAdditions.h
@@ -49,6 +49,11 @@ typedef NS_ENUM(NSUInteger, MASAxisType) {
  */
 - (NSArray *)mas_remakeConstraints:(void (NS_NOESCAPE ^)(MASConstraintMaker *make))block;
 
+/**
+ *  Removes all constraints previously installed on each view in the callee.
+ */
+- (void)mas_removeExistingConstraints;
+
 /**
  *  distribute with fixed spacing
  *
diff --git a/Masonry/NSArray+MASAdditions.m b/Masonry/NSArray+MASAdditions.m
index 831d8cda..e859ce32 100644
--- a/Masonry/NSArray+MASAdditions.m
+++ b/Masonry/NSArray+MASAdditions.m
@@ -38,6 +38,13 @@ - (NSArray *)mas_remakeConstraints:(void(^)(MASConstraintMaker *make))block {
     return constraints;
 }
 
+- (void)mas_removeExistingConstraints {
+    for (MAS_VIEW *view in self) {
+        NSAssert([view isKindOfClass:[MAS_VIEW class]], @"All objects in the array must be views");
+        [view mas_removeExistingConstraints];
+    }
+}
+
 - (void)mas_distributeViewsAlongAxis:(MASAxisType)axisType withFixedSpacing:(CGFloat)fixedSpacing leadSpacing:(CGFloat)leadSpacing tailSpacing:(CGFloat)tailSpacing {
     if (self.count < 2) {
         NSAssert(self.count>1,@"views to distribute need to bigger than one");
diff --git a/Masonry/View+MASAdditions.h b/Masonry/View+MASAdditions.h
index 6fa42a06..ab57c560 100644
--- a/Masonry/View+MASAdditions.h
+++ b/Masonry/View+MASAdditions.h
@@ -98,4 +98,9 @@
  */
 - (NSArray *)mas_remakeConstraints:(void(NS_NOESCAPE ^)(MASConstraintMaker *make))block;
 
+/**
+ *  Removes all constraints previously installed on the callee view.
+ */
+- (void)mas_removeExistingConstraints;
+
 @end
diff --git a/Masonry/View+MASAdditions.m b/Masonry/View+MASAdditions.m
index 5b545ead..5bb84294 100644
--- a/Masonry/View+MASAdditions.m
+++ b/Masonry/View+MASAdditions.m
@@ -7,6 +7,7 @@
 //
 
 #import "View+MASAdditions.h"
+#import "MASViewConstraint.h"
 #import <objc/runtime.h>
 
 @implementation MAS_VIEW (MASAdditions)
@@ -34,6 +35,13 @@ - (NSArray *)mas_remakeConstraints:(void(^)(MASConstraintMaker *make))block {
     return [constraintMaker install];
 }
 
+- (void)mas_removeExistingConstraints {
+    NSArray *installedConstraints = [MASViewConstraint installedConstraintsForView:self];
+    for (MASConstraint *constraint in installedConstraints) {
+        [constraint uninstall];
+    }
+}
+
 #pragma mark - NSLayoutAttribute properties
 
 - (MASViewAttribute *)mas_left {
diff --git a/Masonry/View+MASShorthandAdditions.h b/Masonry/View+MASShorthandAdditions.h
index 9ca6683d..6554fa35 100644
--- a/Masonry/View+MASShorthandAdditions.h
+++ b/Masonry/View+MASShorthandAdditions.h
@@ -52,6 +52,7 @@
 - (NSArray *)makeConstraints:(void(^)(MASConstraintMaker *make))block;
 - (NSArray *)updateConstraints:(void(^)(MASConstraintMaker *make))block;
 - (NSArray *)remakeConstraints:(void(^)(MASConstraintMaker *make))block;
+- (void)removeExistingConstraints;
 
 @end
 
@@ -110,6 +111,9 @@ MAS_ATTR_FORWARD(centerYWithinMargins);
     return [self mas_remakeConstraints:block];
 }
 
+- (void)removeExistingConstraints {
+    [self mas_removeExistingConstraints];
+}
 @end
 
 #endif