From cec5ec9d1e779bc175c932401004810d276b2691 Mon Sep 17 00:00:00 2001
From: Ning Sun <sunng@protonmail.com>
Date: Wed, 17 Oct 2018 23:04:37 +0800
Subject: [PATCH] (feat) added include zero option for truthy check [#240]

---
 src/helpers/helper_each.rs |  2 +-
 src/helpers/helper_if.rs   |  2 +-
 src/helpers/helper_with.rs |  2 +-
 src/value.rs               | 41 +++++++++++++++++++++++++++++++++++---
 4 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/src/helpers/helper_each.rs b/src/helpers/helper_each.rs
index 01b8854d7..5f905620e 100644
--- a/src/helpers/helper_each.rs
+++ b/src/helpers/helper_each.rs
@@ -36,7 +36,7 @@ impl HelperDef for EachHelper {
                     .map(|p| format!("{}/{}", rc.get_path(), p));
 
                 debug!("each value {:?}", value.value());
-                let rendered = match (value.value().is_truthy(), value.value()) {
+                let rendered = match (value.value().is_truthy(false), value.value()) {
                     (true, &Json::Array(ref list)) => {
                         let len = list.len();
                         for (i, _) in list.iter().enumerate().take(len) {
diff --git a/src/helpers/helper_if.rs b/src/helpers/helper_if.rs
index feda72a7b..353190577 100644
--- a/src/helpers/helper_if.rs
+++ b/src/helpers/helper_if.rs
@@ -24,7 +24,7 @@ impl HelperDef for IfHelper {
             .param(0)
             .ok_or_else(|| RenderError::new("Param not found for helper \"if\""))?;
 
-        let mut value = param.value().is_truthy();
+        let mut value = param.value().is_truthy(false);
 
         if !self.positive {
             value = !value;
diff --git a/src/helpers/helper_with.rs b/src/helpers/helper_with.rs
index 1a9ebf9f9..b73f267df 100644
--- a/src/helpers/helper_with.rs
+++ b/src/helpers/helper_with.rs
@@ -29,7 +29,7 @@ impl HelperDef for WithHelper {
         let result = {
             let mut local_rc = rc.derive();
 
-            let not_empty = param.value().is_truthy();
+            let not_empty = param.value().is_truthy(false);
             let template = if not_empty {
                 h.template()
             } else {
diff --git a/src/value.rs b/src/value.rs
index fc29e705a..f5359185c 100644
--- a/src/value.rs
+++ b/src/value.rs
@@ -73,7 +73,7 @@ pub trait JsonRender {
 }
 
 pub trait JsonTruthy {
-    fn is_truthy(&self) -> bool;
+    fn is_truthy(&self, include_zero: bool) -> bool;
 }
 
 impl JsonRender for Json {
@@ -110,10 +110,17 @@ pub fn as_string(src: &Json) -> Option<&str> {
 }
 
 impl JsonTruthy for Json {
-    fn is_truthy(&self) -> bool {
+    fn is_truthy(&self, include_zero: bool) -> bool {
         match *self {
             Json::Bool(ref i) => *i,
-            Json::Number(ref n) => n.as_f64().map(|f| f.is_normal()).unwrap_or(false),
+            Json::Number(ref n) => {
+                if include_zero {
+                    n.as_f64().map(|f| !f.is_nan()).unwrap_or(false)
+                } else {
+                    // there is no inifity in json/serde_json
+                    n.as_f64().map(|f| f.is_normal()).unwrap_or(false)
+                }
+            }
             Json::Null => false,
             Json::String(ref i) => !i.is_empty(),
             Json::Array(ref i) => !i.is_empty(),
@@ -129,3 +136,31 @@ fn test_json_render() {
 
     assert_eq!(raw, thing.render());
 }
+
+#[test]
+fn test_json_number_truthy() {
+    assert!(json!(16i16).is_truthy(false));
+    assert!(json!(16i16).is_truthy(true));
+
+    assert!(json!(0i16).is_truthy(true));
+    assert!(!json!(0i16).is_truthy(false));
+
+    assert!(json!(1.0f64).is_truthy(false));
+    assert!(json!(1.0f64).is_truthy(true));
+
+    assert!(json!(Some(16i16)).is_truthy(false));
+    assert!(json!(Some(16i16)).is_truthy(true));
+
+    assert!(!json!(None as Option<i16>).is_truthy(false));
+    assert!(!json!(None as Option<i16>).is_truthy(true));
+
+    assert!(!json!(std::f64::NAN).is_truthy(false));
+    assert!(!json!(std::f64::NAN).is_truthy(true));
+
+    // there is no infinity in json/serde_json
+    // assert!(json!(std::f64::INFINITY).is_truthy(false));
+    // assert!(json!(std::f64::INFINITY).is_truthy(true));
+
+    // assert!(json!(std::f64::NEG_INFINITY).is_truthy(false));
+    // assert!(json!(std::f64::NEG_INFINITY).is_truthy(true));
+}