6 files changed, 87 insertions, 18 deletions
diff --git a/test-suite/build.rs b/test-suite/build.rs
index ca63946..5a9a55a 100644
--- a/test-suite/build.rs
+++ b/test-suite/build.rs
@@ -4,5 +4,6 @@ use rustc_version::{version, Version};
 fn main() {
     if version().unwrap() >= Version::parse("1.20.0").unwrap() {
         println!(r#"cargo:rustc-cfg=feature="test-quoted-keys-in-macro""#);
+        println!(r#"cargo:rustc-cfg=feature="test-nan-sign""#);
     }
 }
diff --git a/test-suite/tests/float.rs b/test-suite/tests/float.rs
new file mode 100644
index 0000000..6590fe4
--- /dev/null
+++ b/test-suite/tests/float.rs
@@ -0,0 +1,79 @@
+extern crate toml;
+#[macro_use]
+extern crate serde_derive;
+
+use toml::Value;
+
+macro_rules! float_inf_tests {
+    ($ty:ty) => {{
+        #[derive(Serialize, Deserialize)]
+        struct S {
+            sf1: $ty,
+            sf2: $ty,
+            sf3: $ty,
+            sf4: $ty,
+            sf5: $ty,
+            sf6: $ty,
+            sf7: $ty,
+            sf8: $ty,
+        }
+        let inf: S = toml::from_str(
+            r"
+        # infinity
+        sf1 = inf  # positive infinity
+        sf2 = +inf # positive infinity
+        sf3 = -inf # negative infinity
+
+        # not a number
+        sf4 = nan  # actual sNaN/qNaN encoding is implementation specific
+        sf5 = +nan # same as `nan`
+        sf6 = -nan # valid, actual encoding is implementation specific
+
+        # zero
+        sf7 = +0.0
+        sf8 = -0.0
+        ").expect("Parse infinities.");
+
+        assert!(inf.sf1.is_infinite());
+        assert!(inf.sf1.is_sign_positive());
+        assert!(inf.sf2.is_infinite());
+        assert!(inf.sf2.is_sign_positive());
+        assert!(inf.sf3.is_infinite());
+        assert!(inf.sf3.is_sign_negative());
+
+        assert!(inf.sf4.is_nan());
+        assert!(inf.sf4.is_sign_positive());
+        assert!(inf.sf5.is_nan());
+        assert!(inf.sf5.is_sign_positive());
+        assert!(inf.sf6.is_nan());
+        assert!(inf.sf6.is_sign_negative());
+
+        assert_eq!(inf.sf7, 0.0);
+        assert!(inf.sf7.is_sign_positive());
+        assert_eq!(inf.sf8, 0.0);
+        assert!(inf.sf8.is_sign_negative());
+
+        let s = toml::to_string(&inf).unwrap();
+        assert_eq!(
+            s, "\
+sf1 = inf
+sf2 = inf
+sf3 = -inf
+sf4 = nan
+sf5 = nan
+sf6 = -nan
+sf7 = 0.0
+sf8 = -0.0
+"
+        );
+
+        toml::from_str::<Value>(&s).expect("roundtrip");
+    }};
+}
+
+#[test]
+#[cfg(feature = "test-nan-sign")]
+fn float_inf() {
+    float_inf_tests!(f32);
+    float_inf_tests!(f64);
+}
diff --git a/test-suite/tests/invalid-encoder-misc.rs b/test-suite/tests/invalid-encoder-misc.rs
deleted file mode 100644
index 272f58f..0000000
--- a/test-suite/tests/invalid-encoder-misc.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-extern crate toml;
-
-use std::f64;
-
-#[test]
-fn test_invalid_float_encode() {
-    fn bad(value: toml::Value) {
-        assert!(toml::to_string(&value).is_err());
-    }
-
-    bad(toml::Value::Float(f64::INFINITY));
-    bad(toml::Value::Float(f64::NEG_INFINITY));
-    bad(toml::Value::Float(f64::NAN));
-}
diff --git a/test-suite/tests/invalid-misc.rs b/test-suite/tests/invalid-misc.rs
index bb70b97..218be4f 100644
--- a/test-suite/tests/invalid-misc.rs
+++ b/test-suite/tests/invalid-misc.rs
@@ -10,8 +10,7 @@ fn bad() {
     bad("a = 1__1");
     bad("a = 1_");
     bad("''");
-    bad("a = nan");
-    bad("a = -inf");
-    bad("a = inf");
     bad("a = 9e99999");
+    bad("a = \"\u{7f}\"");
+    bad("a = '\u{7f}'");
 }
diff --git a/test-suite/tests/valid/integer.json b/test-suite/tests/valid/integer.json
index 61985a1..86f779f 100644
--- a/test-suite/tests/valid/integer.json
+++ b/test-suite/tests/valid/integer.json
@@ -1,4 +1,6 @@
 {
     "answer": {"type": "integer", "value": "42"},
-    "neganswer": {"type": "integer", "value": "-42"}
+    "neganswer": {"type": "integer", "value": "-42"},
+    "neg_zero": {"type": "integer", "value": "0"},
+    "pos_zero": {"type": "integer", "value": "0"}
 }
diff --git a/test-suite/tests/valid/integer.toml b/test-suite/tests/valid/integer.toml
index c4f6297..2bdca34 100644
--- a/test-suite/tests/valid/integer.toml
+++ b/test-suite/tests/valid/integer.toml
@@ -1,2 +1,4 @@
 answer = 42
 neganswer = -42
+neg_zero = -0
+pos_zero = +0