fix(toml): should use lowercase value for nan (#6638)

Author: mateusvmv

toml/parse_test.ts

@@ -1447,3 +1447,25 @@ readme = { }`;
     assertEquals(actual, expected);
   },
 });
+
+Deno.test({
+  name: "parse() handles NaN and inf",
+  fn() {
+    assertEquals(parse("value = nan").value, NaN);
+    assertEquals(parse("value = +nan").value, NaN);
+    assertEquals(parse("value = -nan").value, NaN);
+    assertEquals(parse("value = inf").value, Infinity);
+    assertEquals(parse("value = +inf").value, Infinity);
+    assertEquals(parse("value = -inf").value, -Infinity);
+    assertThrows(() => parse("value = NaN").value);
+    assertThrows(() => parse("value = +NaN").value);
+    assertThrows(() => parse("value = -NaN").value);
+    assertThrows(() => parse("value = Inf").value);
+    assertThrows(() => parse("value = +Inf").value);
+    assertThrows(() => parse("value = -Inf").value);
+    assertThrows(() => parse("value = nannan"));
+    assertThrows(() => parse("value = -nan_"));
+    assertThrows(() => parse("value = infinf"));
+    assertThrows(() => parse("value = -inf_"));
+  },
+});

toml/stringify.ts

@@ -191,6 +191,9 @@ class Dumper {
     return `${this.#declaration(keys)}${JSON.stringify(value)}`;
   }
   #numberDeclaration(keys: string[], value: number): string {
+    if (Number.isNaN(value)) {
+      return `${this.#declaration(keys)}nan`;
+    }
     switch (value) {
       case Infinity:
         return `${this.#declaration(keys)}inf`;

toml/stringify_test.ts

@@ -187,9 +187,9 @@ reg = "/foo[bar]/"
 sf1 = inf
 sf2 = inf
 sf3 = -inf
-sf4 = NaN
-sf5 = NaN
-sf6 = NaN
+sf4 = nan
+sf5 = nan
+sf6 = nan
 data = [["gamma","delta"],[1,2]]
 hosts = ["alpha","omega"]
 bool = true