NSDateFormatter + NSNumberFormatter sanity checks

groue · Feb 13, 2013 · 18e25c6 · 18e25c6
1 parent 2a25782
commit 18e25c6
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Showing 3 changed files with 239 additions and 13 deletions.
diff --git a/TODO.txt b/TODO.txt
@@ -1,6 +1,5 @@
 1.6.4:
 - update obsolete sample code
-- fix #warnings
 
 Nice to have:
 - document migration path from all previous versions to latest version

diff --git a/src/classes/NSFormatter+GRMustache.m b/src/classes/NSFormatter+GRMustache.m
@@ -33,8 +33,14 @@ @implementation NSFormatter (GRMustache)
  */
 - (id)transformedValue:(id)object
 {
-#warning What about nil?
-#warning What about [NSNull null]?
+    // [NSNumberFormatter stringForObjectValue:] and
+    // [NSDateFormatter stringForObjectValue:] return nil or an empty string for
+    // nil, [NSNull null], and other off-topic values.
+    //
+    // Since nil and empty strings do not render anything, and are false when
+    // controlling boolean sections, we can safely say that formatters do not
+    // have surprising behavior: just use the plain straight
+    // stringForObjectValue: without any special care.
     return [self stringForObjectValue:object];
 }
 
@@ -78,16 +84,9 @@ - (id)mustacheTag:(GRMustacheTag *)tag willRenderObject:(id)object
     // Process {{ value }}, if and only if the value is processable
     if (tag.type == GRMustacheTagTypeVariable) {
 
-        // Preserve nil values
-#warning Is this such a good idea to force nil preservation?
-#warning What about [NSNull null]?
-        if (object == nil) {
-            return nil;
-        }
-
-        NSString *result = [self stringForObjectValue:object];
+        NSString *formatted = [self stringForObjectValue:object];
 
-        if (result == nil) {
+        if (formatted == nil) {
             // NSFormatter documentation for stringForObjectValue: states:
             //
             // > First test the passed-in object to see if it’s of the correct
@@ -100,7 +99,7 @@ - (id)mustacheTag:(GRMustacheTag *)tag willRenderObject:(id)object
             return object;
         }
 
-        return result;
+        return formatted;
     }
 
     // Don't process {{# value }}, {{^ value }}, {{$ value }}

diff --git a/src/tests/Public/v6.4/GRMustacheNSFormatterTest.m b/src/tests/Public/v6.4/GRMustacheNSFormatterTest.m
@@ -150,4 +150,232 @@ - (void)testFormatterRendersSelfAsSomething
     STAssertTrue(rendering.length > 0, @"");
 }
 
+- (void)testNumberFormatterRendersNothingForNil
+{
+    // Check that NSNumberFormatter does not have surprising behavior, and
+    // does not format nil.
+    NSNumberFormatter *formatter = [[[NSNumberFormatter alloc] init] autorelease];
+    formatter.numberStyle = NSNumberFormatterPercentStyle;
+
+    id data = @{ @"format":formatter };
+
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"<>", @"");
+    }
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"NO", @"");
+    }
+}
+
+- (void)testNumberFormatterRendersNothingForNSNull
+{
+    // Check that NSNumberFormatter does not have surprising behavior, and
+    // does not format NSNull.
+    NSNumberFormatter *formatter = [[[NSNumberFormatter alloc] init] autorelease];
+    formatter.numberStyle = NSNumberFormatterPercentStyle;
+
+    id data = @{ @"format":formatter, @"value": [NSNull null] };
+
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"<>", @"");
+    }
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"NO", @"");
+    }
+}
+
+- (void)testNumberFormatterRendersNothingForNSString
+{
+    // Check that NSNumberFormatter does not have surprising behavior, and
+    // does not format NSString.
+    NSNumberFormatter *formatter = [[[NSNumberFormatter alloc] init] autorelease];
+    formatter.numberStyle = NSNumberFormatterPercentStyle;
+
+    {
+        id data = @{ @"format":formatter, @"value":@"1" };
+
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"<>", @"");
+        }
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"NO", @"");
+        }
+    }
+    {
+        id data = @{ @"format":formatter, @"value":@"YES" };
+
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"<>", @"");
+        }
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"NO", @"");
+        }
+    }
+    {
+        id data = @{ @"format":formatter, @"value":@"foo" };
+
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"<>", @"");
+        }
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"NO", @"");
+        }
+    }
+}
+
+- (void)testNumberFormatterRendersNothingForNSDate
+{
+    // Check that NSNumberFormatter does not have surprising behavior, and
+    // does not format NSDate.
+    NSNumberFormatter *formatter = [[[NSNumberFormatter alloc] init] autorelease];
+    formatter.numberStyle = NSNumberFormatterPercentStyle;
+
+    id data = @{ @"format":formatter, @"value": [NSDate date] };
+
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"<>", @"");
+    }
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"NO", @"");
+    }
+}
+
+- (void)testDateFormatterRendersNothingForNil
+{
+    // Check that NSDateFormatter does not have surprising behavior, and
+    // does not format nil.
+    NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
+    formatter.dateStyle = NSDateFormatterFullStyle;
+
+    id data = @{ @"format":formatter };
+
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"<>", @"");
+    }
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"NO", @"");
+    }
+}
+
+- (void)testDateFormatterRendersNothingForNSNull
+{
+    // Check that NSDateFormatter does not have surprising behavior, and
+    // does not format NSNull.
+    NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
+    formatter.dateStyle = NSDateFormatterFullStyle;
+
+    id data = @{ @"format":formatter, @"value": [NSNull null] };
+
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"<>", @"");
+    }
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"NO", @"");
+    }
+}
+
+- (void)testDateFormatterRendersNothingForNSString
+{
+    // Check that NSDateFormatter does not have surprising behavior, and
+    // does not format NSString.
+    NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
+    formatter.dateStyle = NSDateFormatterFullStyle;
+
+    {
+        id data = @{ @"format":formatter, @"value":@"1" };
+
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"<>", @"");
+        }
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"NO", @"");
+        }
+    }
+    {
+        id data = @{ @"format":formatter, @"value":@"YES" };
+
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"<>", @"");
+        }
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"NO", @"");
+        }
+    }
+    {
+        id data = @{ @"format":formatter, @"value":@"foo" };
+
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"<>", @"");
+        }
+        {
+            GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+            NSString *rendering = [template renderObject:data error:NULL];
+            STAssertEqualObjects(rendering, @"NO", @"");
+        }
+    }
+}
+
+- (void)testDateFormatterRendersNothingForNSNumber
+{
+    // Check that NSDateFormatter does not have surprising behavior, and
+    // does not format NSNumber.
+    NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
+    formatter.dateStyle = NSDateFormatterFullStyle;
+
+    id data = @{ @"format":formatter, @"value": [NSNumber numberWithInteger:0] };
+
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"<{{format(value)}}>" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"<>", @"");
+    }
+    {
+        GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:@"{{#format(value)}}YES{{/}}{{^format(value)}}NO{{/}}" error:NULL];
+        NSString *rendering = [template renderObject:data error:NULL];
+        STAssertEqualObjects(rendering, @"NO", @"");
+    }
+}
+
 @end