ScriptInfo: add fallback code for null url & path

Now, the URL and (psuedo-)path can both be null. If that happens,
the getURL() and getPath() methods will both return null. And the
ScriptLanguage will be detected as the highest priority plugin
available (typically Groovy, but depends on runtime classpath).

Author: ctrueden

src/main/java/org/scijava/script/ScriptInfo.java

@@ -232,8 +232,16 @@ public ScriptLanguage getLanguage() {
 		if (scriptLanguage == null) {
 			// infer the language from the script path's extension
 			final String scriptPath = getPath();
-			final String extension = FileUtils.getExtension(scriptPath);
-			scriptLanguage = scriptService.getLanguageByExtension(extension);
+			if (scriptPath != null) {
+				// use language associated with the script path extension
+				final String extension = FileUtils.getExtension(scriptPath);
+				scriptLanguage = scriptService.getLanguageByExtension(extension);
+			}
+			else {
+				// use the highest priority language
+				final List<ScriptLanguage> langs = scriptService.getLanguages();
+				if (langs != null && !langs.isEmpty()) scriptLanguage = langs.get(0);
+			}
 		}
 		return scriptLanguage;
 	}
@@ -371,7 +379,7 @@ public void setContext(final Context context) {
 
 	@Override
 	public String getIdentifier() {
-		return "script:" + path;
+		return "script:" + (path == null ? "<inline>" : path);
 	}
 
 	// -- Locatable methods --
@@ -403,6 +411,7 @@ public String getVersion() {
 
 	private URL url(final URL u, final String p) {
 		if (u != null) return u;
+		if (p == null) return null;
 		try {
 			return new File(p).toURI().toURL();
 		}
@@ -413,7 +422,8 @@ private URL url(final URL u, final String p) {
 	}
 
 	private String path(final URL u, final String p) {
-		return p == null ? u.getPath() : p;
+		if (p != null) return p;
+		return u == null ? null : u.getPath();
 	}
 
 	private void parseParam(final String param) throws ScriptException {