Print warning when glob is too general

Author: dnestoro

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jdk/resources/CompressedGlobTrie/CompressedGlobTrie.java

@@ -109,6 +109,7 @@ public static <C> GlobTrieNode<C> build(List<GlobWithInfo<C>> patterns) {
             if (!invalidPatterns.isEmpty()) {
                 StringBuilder sb = new StringBuilder("Error: invalid glob patterns found:" + System.lineSeparator());
                 invalidPatterns.forEach(msg -> sb.append(msg).append(System.lineSeparator()));
+
                 throw UserError.abort(sb.toString());
             }
 

substratevm/src/com.oracle.svm.util/src/com/oracle/svm/util/GlobUtils.java

@@ -42,11 +42,12 @@ private GlobUtils() {
     public static final String SAME_LEVEL_IDENTIFIER = "#";
     private static final Pattern threeConsecutiveStarsRegex = Pattern.compile(".*[*]{3,}.*");
     private static final Pattern emptyLevelsRegex = Pattern.compile(".*/{2,}.*");
+    private static final String ALL_UNNAMED = "ALL_UNNAMED";
 
     public static String transformToTriePath(String resource, String module) {
         String resolvedModuleName;
         if (module == null || module.isEmpty()) {
-            resolvedModuleName = "ALL_UNNAMED";
+            resolvedModuleName = ALL_UNNAMED;
         } else {
             resolvedModuleName = StringUtil.toSlashSeparated(module);
         }
@@ -104,15 +105,25 @@ public static String validatePattern(String pattern) {
             escapeMode = current == '\\';
         }
 
-        // check if pattern contains ** without previous Literal parent. Example: */**/... or **/...
-        outer: for (List<GlobToken> levelTokens : tokenize(pattern)) {
-            for (GlobToken token : levelTokens) {
-                if (token.kind == GlobToken.Kind.LITERAL) {
-                    break outer;
-                } else if (token.kind == GlobToken.Kind.STAR_STAR) {
-                    sb.append("Pattern contains ** without previous literal. " +
-                                    "This pattern is too generic and therefore can match many resources. " +
-                                    "Please make the pattern more specific by adding non-generic level before ** level.");
+        // check if pattern (that matches something from classpath) contains ** without previous
+        // Literal parent. Example: */**/... or **/...
+        if (pattern.startsWith(ALL_UNNAMED)) {
+            List<List<GlobToken>> patternParts = tokenize(pattern);
+
+            // remove ALL_UNNAMED prefix
+            patternParts.removeFirst();
+
+            // check glob without module prefix
+            outer: for (List<GlobToken> levelTokens : patternParts) {
+                for (GlobToken token : levelTokens) {
+                    if (token.kind == GlobToken.Kind.LITERAL) {
+                        break outer;
+                    } else if (token.kind == GlobToken.Kind.STAR_STAR) {
+                        String patternWithoutModule = pattern.substring(ALL_UNNAMED.length() + 1);
+                        LogUtils.warning("Pattern: " + patternWithoutModule + " contains ** without previous literal. " +
+                                        "This pattern is too generic and therefore can match many resources. " +
+                                        "Please make the pattern more specific by adding non-generic level before ** level.");
+                    }
                 }
             }
         }