From 6328beff8974f197adc10a15dd0fc03493ce6bf4 Mon Sep 17 00:00:00 2001
From: Yin Jifeng <yinjifeng@bytedance.com>
Date: Wed, 18 Dec 2019 11:43:35 +0800
Subject: [PATCH] fix(isEmpty): treat golang zero values as falsy

---
 mustache.go      |  8 +++-----
 mustache_test.go | 17 ++++++++++++++---
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/mustache.go b/mustache.go
index c545e4e..18dd90b 100644
--- a/mustache.go
+++ b/mustache.go
@@ -541,15 +541,13 @@ func isEmpty(v reflect.Value) bool {
 		return true
 	}
 	switch val := valueInd; val.Kind() {
-	case reflect.Bool:
-		return !val.Bool()
-	case reflect.Slice:
+	case reflect.Array, reflect.Slice:
 		return val.Len() == 0
 	case reflect.String:
 		return len(strings.TrimSpace(val.String())) == 0
+	default:
+		return valueInd.IsZero()
 	}
-
-	return false
 }
 
 func indirect(v reflect.Value) reflect.Value {
diff --git a/mustache_test.go b/mustache_test.go
index 8b2085a..a70c1d0 100644
--- a/mustache_test.go
+++ b/mustache_test.go
@@ -125,9 +125,20 @@ var tests = []Test{
 	{`{{Name}}`, &User{"Mike", 1}, "Mike", nil},
 	{"{{#users}}\n{{Name}}\n{{/users}}", map[string]interface{}{"users": makeVector(2)}, "Mike\nMike\n", nil},
 	{"{{#users}}\r\n{{Name}}\r\n{{/users}}", map[string]interface{}{"users": makeVector(2)}, "Mike\r\nMike\r\n", nil},
-	{"{{#users}}Hi {{Name}}{{/users}}", map[string]interface{}{"users": ""}, "", nil},
-	{"{{#users}}Hi {{Name}}{{/users}}", map[string]interface{}{"users": []interface{}{}}, "", nil},
-	{"{{#users}}Hi {{Name}}{{/users}}", map[string]interface{}{"users": false}, "", nil},
+
+	//falsy: golang zero values
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": nil}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": false}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": 0}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": 0.0}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": ""}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": Data{}}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": []interface{}{}}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": [0]interface{}{}}, "", nil},
+	//falsy: special cases we disagree with golang
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": "\t"}, "", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": []interface{}{0}}, "Hi 0", nil},
+	{"{{#a}}Hi {{.}}{{/a}}", map[string]interface{}{"a": [1]interface{}{0}}, "Hi 0", nil},
 
 	//section does not exist
 	{`{{#has}}{{/has}}`, &User{"Mike", 1}, "", nil},