Merge pull request #6 from mailgun/cclark/dev

PIP:1374: Add ifLt helper

helper.go

@@ -35,6 +35,7 @@ func init() {
 	RegisterHelper("lookup", lookupHelper)
 	RegisterHelper("equal", equalHelper)
 	RegisterHelper("ifGt", ifGtHelper)
+	RegisterHelper("ifLt", ifLtHelper)
 }
 
 // RegisterHelper registers a global helper. That helper will be available to all templates.
@@ -311,11 +312,11 @@ func ifGtHelper(a, b interface{}, options *Options) interface{} {
 
 	if aFloat, err = floatValue(a); err != nil {
 		// TODO: Log conversion failure.
-		return ""
+		return options.Inverse()
 	}
 	if bFloat, err = floatValue(b); err != nil {
 		// TODO: Log conversion failure
-		return ""
+		return options.Inverse()
 	}
 
 	if aFloat > bFloat {
@@ -325,6 +326,26 @@ func ifGtHelper(a, b interface{}, options *Options) interface{} {
 	return options.Inverse()
 }
 
+func ifLtHelper(a, b interface{}, options *Options) interface{} {
+	var aFloat, bFloat float64
+	var err error
+
+	if aFloat, err = floatValue(a); err != nil {
+		// TODO: Log conversion failure.
+		return options.Inverse()
+	}
+	if bFloat, err = floatValue(b); err != nil {
+		// TODO: Log conversion failure
+		return options.Inverse()
+	}
+
+	if aFloat < bFloat {
+		return options.Fn()
+	}
+	// Evaluate possible else condition.
+	return options.Inverse()
+}
+
 // #unless block helper
 func unlessHelper(conditional interface{}, options *Options) interface{} {
 	if options.isIncludableZero() || IsTrue(conditional) {

helper_test.go

@@ -236,6 +236,76 @@ var helperTests = []Test{
 		nil, nil, nil,
 		`foo is not greater than bar`,
 	},
+	{
+		"#ifGt helper non-numbers",
+		`{{#ifGt foo bar}}foo is greater than bar{{/ifGt}}`,
+		map[string]interface{}{"foo": "foo", "bar": "bar"},
+		nil, nil, nil,
+		``,
+	},
+	{
+		"#ifGt helper non-numbers with else condition",
+		`{{#ifGt foo bar}}foo is greater than bar{{else}}foo or bar are not numbers{{/ifGt}}`,
+		map[string]interface{}{"foo": "foo", "bar": "bar"},
+		nil, nil, nil,
+		`foo or bar are not numbers`,
+	},
+	{
+		"#ifLt helper with true literal",
+		`{{#ifLt foo 10}}foo is less than 10{{/ifLt}}`,
+		map[string]interface{}{"foo": 5},
+		nil, nil, nil,
+		`foo is less than 10`,
+	},
+	{
+		"#ifLt helper with false literal",
+		`{{#ifLt foo 10}}foo is less than 10{{/ifLt}}`,
+		map[string]interface{}{"foo": 15},
+		nil, nil, nil,
+		``,
+	},
+	{
+		"#ifLt helper with true literal from params",
+		`{{#ifLt foo bar}}foo is less than bar{{/ifLt}}`,
+		map[string]interface{}{"foo": 0, "bar": 5},
+		nil, nil, nil,
+		`foo is less than bar`,
+	},
+	{
+		"#ifLt helper with string comparison",
+		`{{#ifLt foo bar}}foo is less than bar{{/ifLt}}`,
+		map[string]interface{}{"foo": "0", "bar": "5"},
+		nil, nil, nil,
+		`foo is less than bar`,
+	},
+	{
+		"#ifLt helper with false literal from params",
+		`{{#ifLt foo bar}}foo is less than bar{{/ifLt}}`,
+		map[string]interface{}{"foo": 0, "bar": 5},
+		nil, nil, nil,
+		`foo is less than bar`,
+	},
+	{
+		"#ifLt helper with else condition",
+		`{{#ifLt foo bar}}foo is less than bar{{else}}foo is not less than bar{{/ifLt}}`,
+		map[string]interface{}{"foo": 6, "bar": 5},
+		nil, nil, nil,
+		`foo is not less than bar`,
+	},
+	{
+		"#ifLt helper non-numbers",
+		`{{#ifLt foo bar}}foo is less than bar{{/ifLt}}`,
+		map[string]interface{}{"foo": "foo", "bar": "bar"},
+		nil, nil, nil,
+		``,
+	},
+	{
+		"#ifLt helper non-numbers with else condition",
+		`{{#ifLt foo bar}}foo is greater than bar{{else}}foo or bar are not numbers{{/ifLt}}`,
+		map[string]interface{}{"foo": "foo", "bar": "bar"},
+		nil, nil, nil,
+		`foo or bar are not numbers`,
+	},
 	{
 		"#equal helper inside HTML tag",
 		`<option value="test" {{#equal value "test"}}selected{{/equal}}>Test</option>`,