fix parsing name and quoted bugs

PRL-PRG · Jun 28, 2024 · 5e2fb28 · 5e2fb28
1 parent e5a0de6
commit 5e2fb28
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Showing 3 changed files with 21 additions and 4 deletions.
diff --git a/src/main/java/org/prlprg/parseprint/Scanner.java b/src/main/java/org/prlprg/parseprint/Scanner.java
@@ -309,9 +309,9 @@ public String readQuoted(char quote) {
                 case 'r' -> sb.append('\r');
                 case 't' -> sb.append('\t');
                 case '"' -> sb.append('"');
-                case '\\' -> sb.append('\\');
                 case '\'' -> sb.append('\'');
                 case '`' -> sb.append('`');
+                case '\\' -> sb.append('\\');
                 case 'x' -> {
                   var hex = readFixedLength(2);
                   try {
@@ -362,7 +362,13 @@ public String readQuotedLiterally(char quote) {
               return sb.toString();
             } else if (c == '\\') {
               switch (readChar()) {
-                case 'n', 'r', 't', '"', '\\', '\'', '`' -> {}
+                case 'n' -> sb.append('n');
+                case 'r' -> sb.append('r');
+                case 't' -> sb.append('t');
+                case '"' -> sb.append('"');
+                case '\'' -> sb.append('\'');
+                case '`' -> sb.append('`');
+                case '\\' -> sb.append('\\');
                 case 'x' -> {
                   var hex = readFixedLength(2);
                   try {

diff --git a/src/main/java/org/prlprg/primitive/Names.java b/src/main/java/org/prlprg/primitive/Names.java
@@ -1,6 +1,7 @@
 package org.prlprg.primitive;
 
 import com.google.common.collect.ImmutableList;
+import java.util.regex.Pattern;
 import org.prlprg.parseprint.ParseException;
 import org.prlprg.parseprint.PrettyPrintWriter;
 import org.prlprg.parseprint.Scanner;
@@ -27,7 +28,7 @@ public static String quoteIfNecessary(String s) {
     if (s.isEmpty()) {
       throw new IllegalArgumentException("empty string is reserved for special symbols");
     }
-    return isValidUnquoted(s) ? s : PrettyPrintWriter.use(w -> w.writeQuoted('`', s));
+    return isValid(s) ? s : PrettyPrintWriter.use(w -> w.writeQuoted('`', s));
   }
 
   /**
@@ -41,6 +42,8 @@ public static String unquoteIfNecessary(String s) {
         : s;
   }
 
+  private static final Pattern UNESCAPED_NOT_END_BACKTICK = Pattern.compile("(?<!\\\\)`(?!$)");
+
   /**
    * Whether the string {@linkplain #isValidUnquoted(String) is valid unquoted}, or is in quotes and
    * not empty.
@@ -50,7 +53,7 @@ public static boolean isValid(String s) {
         || (s.startsWith("`")
             && s.endsWith("`")
             && s.length() > 2
-            && !s.substring(1, s.length() - 1).replaceAll("\\`", "").contains("`"));
+            && !UNESCAPED_NOT_END_BACKTICK.matcher(s).find(1));
   }
 
   /**

diff --git a/src/test/java/org/prlprg/parseprint/ScannerTests.java b/src/test/java/org/prlprg/parseprint/ScannerTests.java
@@ -18,4 +18,12 @@ public void testReadPastEndOfLine() {
     assertEquals("\n", scanner2.readPastEndOfLine());
     assertEquals("3", scanner2.readPastEndOfLine());
   }
+
+  @Test
+  public void testReadQuoted() {
+    var scanner = new Scanner("\"\\\"Hello\\\", \\\"world!\\\"\"");
+    assertEquals("\"Hello\", \"world!\"", scanner.readQuoted('"'));
+    scanner = new Scanner("\"\\\"Hello\\\", \\\"world!\\\"\"");
+    assertEquals("\"\\\"Hello\\\", \\\"world!\\\"\"", scanner.readQuotedLiterally('"'));
+  }
 }