[ruby/prism] Fix an error when specifying the parsing version `latest`

This PR fixes following error when using `version: latest` argument.

```console
$ ruby -rprism -e "p Prism.parse('-> { it }', version: 'latest')"
-e:1:in `parse': invalid version: latest (ArgumentError)

p Prism.parse('-> { it }', version: 'latest')
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        from -e:1:in `<main>'
```

The argument `version: latest` in the added test is commented as potentially being
better replaced with `version: 3.4.0` in the future.

https://github.com/ruby/prism/commit/27b5c933cb

1 files changed, 7 insertions, 9 deletions

diff --git a/prism/options.c b/prism/options.c
index 4187abf9fa..ae5b5a8d3c 100644
--- a/prism/options.c
+++ b/prism/options.c
@@ -44,16 +44,14 @@ pm_options_version_set(pm_options_t *options, const char *version, size_t length
         return true;
     }
 
-    if (length == 5) {
-        if (strncmp(version, "3.3.0", 5) == 0) {
-            options->version = PM_OPTIONS_VERSION_CRUBY_3_3_0;
-            return true;
-        }
+    if (length == 5 && strncmp(version, "3.3.0", length) == 0) {
+        options->version = PM_OPTIONS_VERSION_CRUBY_3_3_0;
+        return true;
+    }
 
-        if (strncmp(version, "latest", 6) == 0) {
-            options->version = PM_OPTIONS_VERSION_LATEST;
-            return true;
-        }
+    if (length == 6 && strncmp(version, "latest", length) == 0) {
+        options->version = PM_OPTIONS_VERSION_LATEST;
+        return true;
     }
 
     return false;