Improve error message when parsing unquoted string (#385)

* Improve error message when parsing unquoted string

* Remove conversion to lowercase in parse_keylike()

Converting keys to lowercase goes against
TOML specification for floats.

* Change error message for unquoted string

3 files changed, 19 insertions, 10 deletions

diff --git a/test-suite/tests/datetime.rs b/test-suite/tests/datetime.rs
index 74b5939..6c08748 100644
--- a/test-suite/tests/datetime.rs
+++ b/test-suite/tests/datetime.rs
@@ -68,15 +68,15 @@ fn bad_times() {
     );
     bad!(
         "foo = T",
-        "failed to parse datetime for key `foo` at line 1 column 7"
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
     );
     bad!(
         "foo = T.",
-        "expected newline, found a period at line 1 column 8"
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
     );
     bad!(
         "foo = TZ",
-        "failed to parse datetime for key `foo` at line 1 column 7"
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
     );
     bad!(
         "foo = 1997-09-09T09:09:09.09+",
diff --git a/test-suite/tests/invalid.rs b/test-suite/tests/invalid.rs
index ccc9338..f04d860 100644
--- a/test-suite/tests/invalid.rs
+++ b/test-suite/tests/invalid.rs
@@ -197,7 +197,7 @@ test!(
 test!(
     text_after_array_entries,
     include_str!("invalid/text-after-array-entries.toml"),
-    "invalid number at line 2 column 46"
+    "invalid TOML value, did you mean to use a quoted string? at line 2 column 46"
 );
 test!(
     text_after_integer,
@@ -222,5 +222,5 @@ test!(
 test!(
     text_in_array,
     include_str!("invalid/text-in-array.toml"),
-    "invalid number at line 3 column 3"
+    "invalid TOML value, did you mean to use a quoted string? at line 3 column 3"
 );
diff --git a/test-suite/tests/parser.rs b/test-suite/tests/parser.rs
index eab9f5a..169df79 100644
--- a/test-suite/tests/parser.rs
+++ b/test-suite/tests/parser.rs
@@ -491,7 +491,10 @@ fn number_underscores() {
 fn bad_underscores() {
     bad!("foo = 0_", "invalid number at line 1 column 7");
     bad!("foo = 0__0", "invalid number at line 1 column 7");
-    bad!("foo = __0", "invalid number at line 1 column 7");
+    bad!(
+        "foo = __0",
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
+    );
     bad!("foo = 1_0_", "invalid number at line 1 column 7");
 }
 
@@ -537,14 +540,20 @@ fn booleans() {
 
     bad!(
         "foo = true2",
-        "failed to parse datetime for key `foo` at line 1 column 7"
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
+    );
+    bad!(
+        "foo = false2",
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
     );
-    bad!("foo = false2", "invalid number at line 1 column 7");
     bad!(
         "foo = t1",
-        "failed to parse datetime for key `foo` at line 1 column 7"
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
+    );
+    bad!(
+        "foo = f2",
+        "invalid TOML value, did you mean to use a quoted string? at line 1 column 7"
     );
-    bad!("foo = f2", "invalid number at line 1 column 7");
 }
 
 #[test]