Improve CamelCaseFunctionNameSanitizer

Function names are now correctly formatted if they contain acronyms. The
name sanitizer also will not change the case of words that are already
pascal or camel case in the input.

Author: friederbluemle

core/src/main/java/cucumber/runtime/snippets/CamelCaseFunctionNameSanitizer.java

@@ -17,7 +17,7 @@ public String sanitizeFunctionName(String functionName) {
         sanitized.append(words[0].toLowerCase());
 
         for (int i = 1; i < words.length; i++) {
-            sanitized.append(capitalize(words[i].toLowerCase()));
+            sanitized.append(sanitizeWord(words[i]));
         }
 
         return sanitized.toString();
@@ -26,4 +26,28 @@ public String sanitizeFunctionName(String functionName) {
     private String capitalize(String line) {
         return line.length() > 0 ? Character.toUpperCase(line.charAt(0)) + line.substring(1) : "";
     }
+
+    private boolean isUpperCaseAcronym(String word) {
+        if (word == null || word.length() < 2) {
+            return false;
+        }
+
+        for (char c : word.toCharArray()) {
+            if (Character.isLowerCase(c)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private String sanitizeWord(String word) {
+        if (word == null) {
+            return "";
+        } else if (word.length() == 2 && isUpperCaseAcronym(word)) {
+            return word;
+        } else {
+            return capitalize(isUpperCaseAcronym(word) ? word.toLowerCase() : word);
+        }
+    }
 }

core/src/test/java/cucumber/runtime/snippets/CamelCaseFunctionNameSanitizerTest.java

@@ -14,13 +14,31 @@ public void testSanitizeFunctionName() {
         String functionName = "I am a function name";
         String expected = "iAmAFunctionName";
         String actual = generator.sanitizeFunctionName(functionName);
-
         assertEquals(expected, actual);
 
         functionName = "Function name with multiple  spaces";
         expected = "functionNameWithMultipleSpaces";
         actual = generator.sanitizeFunctionName(functionName);
+        assertEquals(expected, actual);
+
+        functionName = "Function name with pascalCase word";
+        expected = "functionNameWithPascalCaseWord";
+        actual = generator.sanitizeFunctionName(functionName);
+        assertEquals(expected, actual);
+
+        functionName = "Function name with CamelCase word";
+        expected = "functionNameWithCamelCaseWord";
+        actual = generator.sanitizeFunctionName(functionName);
+        assertEquals(expected, actual);
+
+        functionName = "Function name with multi char acronym HTTP Server";
+        expected = "functionNameWithMultiCharAcronymHttpServer";
+        actual = generator.sanitizeFunctionName(functionName);
+        assertEquals(expected, actual);
 
+        functionName = "Function name with two char acronym US";
+        expected = "functionNameWithTwoCharAcronymUS";
+        actual = generator.sanitizeFunctionName(functionName);
         assertEquals(expected, actual);
     }
 }