fix: handle faulty imports (#12793)

Do not throw silently for incompatible
import paths. Fix comment removal
for JS files to accept ' as string.

fixes #12765

flow-server/src/main/java/com/vaadin/flow/internal/StringUtil.java

@@ -34,15 +34,32 @@ public final class StringUtil {
      * Comment parser state enumeration.
      */
     private enum State {
-        NORMAL, IN_LINE_COMMENT, IN_BLOCK_COMMENT, IN_STRING
+        NORMAL, IN_LINE_COMMENT, IN_BLOCK_COMMENT, IN_STRING, IN_STRING_APOSTROPHE
     }
 
     /**
      * Removes comments (block comments and line comments) from the JS code.
      *
+     * @param code
+     *            code to clean comments from
      * @return the code with removed comments
      */
-    public final static String removeComments(String code) {
+    public static String removeComments(String code) {
+        return removeComments(code, false);
+    }
+
+    /**
+     * Removes comments (block comments and line comments) from the JS code.
+     *
+     * @param code
+     *            code to clean comments from
+     * @param useStringApostrophe
+     *            if {@code true} then ' is also considered a string and
+     *            comments will not be considered inside it
+     * @return the code with removed comments
+     */
+    public static String removeComments(String code,
+            boolean useStringApostrophe) {
         State state = State.NORMAL;
         StringBuilder result = new StringBuilder();
         Map<String, Character> replacements = new HashMap<>();
@@ -65,6 +82,8 @@ public final static String removeComments(String code) {
                     result.append(character);
                     if (character.equals("\"")) {
                         state = State.IN_STRING;
+                    } else if (useStringApostrophe && character.equals("'")) {
+                        state = State.IN_STRING_APOSTROPHE;
                     }
                 }
                 break;
@@ -76,6 +95,14 @@ public final static String removeComments(String code) {
                     result.append(scanner.next());
                 }
                 break;
+            case IN_STRING_APOSTROPHE:
+                result.append(character);
+                if (character.equals("'")) {
+                    state = State.NORMAL;
+                } else if (character.equals("\\") && scanner.hasNext()) {
+                    result.append(scanner.next());
+                }
+                break;
             case IN_LINE_COMMENT:
                 if (character.equals("\n")) {
                     result.append(character);

flow-server/src/main/java/com/vaadin/flow/server/frontend/AbstractUpdateImports.java

@@ -22,6 +22,7 @@
 import java.nio.charset.MalformedInputException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
+import java.nio.file.InvalidPathException;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -544,7 +545,10 @@ private void visitImportsRecursively(Path filePath, String path,
             if (file == null && !importedPath.startsWith("./")) {
                 // In case such file doesn't exist it may be external: inside
                 // node_modules folder
-                file = getFile(getNodeModulesDir(), resolvedPath);
+                file = getFile(getNodeModulesDir(), importedPath);
+                if (!file.exists()) {
+                    file = null;
+                }
                 resolvedPath = importedPath;
             }
             if (file == null) {
@@ -602,12 +606,19 @@ private String resolve(String importedPath, Path moduleFile, String path) {
         String pathPrefix = moduleFile.toString();
         pathPrefix = pathPrefix.substring(0,
                 pathPrefix.length() - path.length());
-        String resolvedPath = moduleFile.getParent().resolve(importedPath)
-                .toString();
-        if (resolvedPath.startsWith(pathPrefix)) {
-            resolvedPath = resolvedPath.substring(pathPrefix.length());
+        try {
+            String resolvedPath = moduleFile.getParent().resolve(importedPath)
+                    .toString();
+            if (resolvedPath.startsWith(pathPrefix)) {
+                resolvedPath = resolvedPath.substring(pathPrefix.length());
+            }
+            return resolvedPath;
+        } catch (InvalidPathException ipe) {
+            getLogger().error("Invalid import '{}' in file '{}'", importedPath,
+                    moduleFile);
+            getLogger().debug("Failed to resolve path.", ipe);
         }
-        return resolvedPath;
+        return importedPath;
     }
 
     private String normalizePath(String path) {

flow-server/src/main/java/com/vaadin/flow/server/frontend/ImportExtractor.java

@@ -86,7 +86,7 @@ List<String> getImportedPaths() {
      * @return the code with removed comments
      */
     String removeComments() {
-        return StringUtil.removeComments(content);
+        return StringUtil.removeComments(content, true);
     }
 
     /**

flow-server/src/test/java/com/vaadin/flow/internal/StringUtilTest.java

@@ -66,7 +66,45 @@ public void commentRemoval_emojiInString_removalDoesnotThrowResultIsTheSame() {
     @Test
     public void removeComments_commentsWithAsterisksInside_commentIsRemoved() {
         String result = StringUtil.removeComments("/* comment **/ ;");
-        Assert.assertEquals(result, " ;");
+        Assert.assertEquals(" ;", result);
     }
 
-}
+    @Test
+    public void removeJsComments_handlesApostropheAsInString() {
+        String httpImport = "import 'http://localhost:56445/files/transformed/@vaadin/vaadin-text-field/vaadin-text-field.js';";
+
+        Assert.assertEquals("Nothing shoiuld be removed for import", httpImport,
+                StringUtil.removeComments(httpImport, true));
+
+        String result = StringUtil.removeComments("/* comment **/ ;", true);
+        Assert.assertEquals(" ;", result);
+
+        String singleLineBlock = StringUtil.removeComments(
+                "return html`/* single line block comment*/`;", true);
+
+        Assert.assertEquals("return html``;", singleLineBlock);
+
+        String blockComment = StringUtil
+                .removeComments("return html`/* block with new lines\n"
+                        + "* still in my/their block */`;", true);
+        Assert.assertEquals("return html``;", blockComment);
+
+        String newLineSingleBlock = StringUtil
+                .removeComments("return html`/* not here \n*/`;", true);
+        Assert.assertEquals("return html``;", newLineSingleBlock);
+
+        String noComments = "<vaadin-text-field label=\"Nats Url(s)\" placeholder=\"nats://server:port\" id=\"natsUrlTxt\" style=\"width:100%\"></vaadin-text-field>`";
+        Assert.assertEquals(noComments,
+                StringUtil.removeComments(noComments, true));
+
+        String lineComment = StringUtil
+                .removeComments("return html`// this line comment\n`;", true);
+        Assert.assertEquals("return html`\n`;", lineComment);
+
+        String mixedComments = StringUtil.removeComments(
+                "return html`/* not here \n*/\nCode;// neither this\n"
+                        + "/* this should // be fine\n* to remove / */`;",
+                true);
+        Assert.assertEquals("return html`\nCode;\n`;", mixedComments);
+    }
+}