add time.Time support to Value and comparison operators (#232)

Fixes #231

parser_expression.go

@@ -180,23 +180,37 @@ func (expr *relationalExpression) Evaluate(ctx *ExecutionContext) (*Value, *Erro
 			if v1.IsFloat() || v2.IsFloat() {
 				return AsValue(v1.Float() <= v2.Float()), nil
 			}
+			if v1.IsTime() && v2.IsTime() {
+				tm1, tm2 := v1.Time(), v2.Time()
+				return AsValue(tm1.Before(tm2) || tm1.Equal(tm2)), nil
+			}
 			return AsValue(v1.Integer() <= v2.Integer()), nil
 		case ">=":
 			if v1.IsFloat() || v2.IsFloat() {
 				return AsValue(v1.Float() >= v2.Float()), nil
 			}
+			if v1.IsTime() && v2.IsTime() {
+				tm1, tm2 := v1.Time(), v2.Time()
+				return AsValue(tm1.After(tm2) || tm1.Equal(tm2)), nil
+			}
 			return AsValue(v1.Integer() >= v2.Integer()), nil
 		case "==":
 			return AsValue(v1.EqualValueTo(v2)), nil
 		case ">":
 			if v1.IsFloat() || v2.IsFloat() {
 				return AsValue(v1.Float() > v2.Float()), nil
 			}
+			if v1.IsTime() && v2.IsTime() {
+				return AsValue(v1.Time().After(v2.Time())), nil
+			}
 			return AsValue(v1.Integer() > v2.Integer()), nil
 		case "<":
 			if v1.IsFloat() || v2.IsFloat() {
 				return AsValue(v1.Float() < v2.Float()), nil
 			}
+			if v1.IsTime() && v2.IsTime() {
+				return AsValue(v1.Time().Before(v2.Time())), nil
+			}
 			return AsValue(v1.Integer() < v2.Integer()), nil
 		case "!=", "<>":
 			return AsValue(!v1.EqualValueTo(v2)), nil

pongo2_template_test.go

@@ -135,6 +135,8 @@ Yep!`,
 		"misc_list":          []interface{}{"Hello", 99, 3.14, "good"},
 		"escape_text":        "This is \\a Test. \"Yep\". 'Yep'.",
 		"xss":                "<script>alert(\"uh oh\");</script>",
+		"time1":              time1,
+		"time2":              time2,
 		"intmap": map[int]string{
 			1: "one",
 			5: "five",

template_tests/time.tpl

@@ -0,0 +1,7 @@
+{% if simple.time1 == simple.time1 %}equal{% else %}not equal{% endif %}
+{% if simple.time1 > simple.time2 %}greater{% else %}not greater{% endif %}
+{% if simple.time2 < simple.time1 %}lower{% else %}not lower{% endif %}
+{% if simple.time1 >= simple.time2 %}greater or equal (greater){% else %}not greater or equal (greater){% endif %}
+{% if simple.time1 >= simple.time1 %}greater or equal (equal){% else %}not greater or equal (equal){% endif %}
+{% if simple.time2 <= simple.time1 %}lower or equal (lower){% else %}not lower or equal (lower){% endif %}
+{% if simple.time2 <= simple.time2 %}lower or equal (equal){% else %}not lower or equal (equal){% endif %}

template_tests/time.tpl.out

@@ -0,0 +1,7 @@
+equal
+greater
+lower
+greater or equal (greater)
+greater or equal (equal)
+lower or equal (lower)
+lower or equal (equal)

value.go

@@ -6,6 +6,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"time"
 )
 
 type Value struct {
@@ -76,6 +77,12 @@ func (v *Value) IsNumber() bool {
 	return v.IsInteger() || v.IsFloat()
 }
 
+// IsTime checks whether the underlying value is a time.Time.
+func (v *Value) IsTime() bool {
+	_, ok := v.Interface().(time.Time)
+	return ok
+}
+
 // IsNil checks whether the underlying value is NIL
 func (v *Value) IsNil() bool {
 	//fmt.Printf("%+v\n", v.getResolvedValue().Type().String())
@@ -185,6 +192,16 @@ func (v *Value) Bool() bool {
 	}
 }
 
+// Time returns the underlying value as time.Time.
+// If the underlying value is not a time.Time, it returns the zero value of time.Time.
+func (v *Value) Time() time.Time {
+	tm, ok := v.Interface().(time.Time)
+	if ok {
+		return tm
+	}
+	return time.Time{}
+}
+
 // IsTrue tries to evaluate the underlying value the Pythonic-way:
 //
 // Returns TRUE in one the following cases:
@@ -470,6 +487,9 @@ func (v *Value) EqualValueTo(other *Value) bool {
 	if v.IsInteger() && other.IsInteger() {
 		return v.Integer() == other.Integer()
 	}
+	if v.IsTime() && other.IsTime() {
+		return v.Time().Equal(other.Time())
+	}
 	return v.Interface() == other.Interface()
 }