Escape current character output

2024-03-12 13:19:48 +01:00 · 2024-03-12 13:19:48 +01:00 · 57b2e54b5a
parent ff4b1a7656
commit 57b2e54b5a
7 changed files with 110 additions and 65 deletions
--- a/gson/src/main/java/com/google/gson/stream/JsonReader.java
+++ b/gson/src/main/java/com/google/gson/stream/JsonReader.java
@ -22,6 +22,8 @@ import com.google.gson.Strictness;
 import com.google.gson.internal.DefaultConfig;
 import com.google.gson.internal.JsonReaderInternalAccess;
 import com.google.gson.internal.TroubleshootingGuide;
+import com.google.gson.util.StringEscapeUtil;
+
 import java.io.Closeable;
 import java.io.EOFException;
 import java.io.IOException;
@ -1611,7 +1613,11 @@ public class JsonReader implements Closeable {
  private String locationString() {
    int line = lineNumber + 1;
    int column = pos - lineStart + 1;
-    String charInterjection = pos < buffer.length ? " (char '" + buffer[pos] + "')" : "";
+    String replacement = StringEscapeUtil.getReplacement(buffer[pos]);
+    if (replacement == null)  {
+      replacement = String.valueOf(buffer[pos]);
+    }
+    String charInterjection = pos < buffer.length ? " (char '" + replacement + "')" : "";
    return " at line " + line + " column " + column + charInterjection + " path " + getPath();
  }

--- a/gson/src/main/java/com/google/gson/stream/JsonWriter.java
+++ b/gson/src/main/java/com/google/gson/stream/JsonWriter.java
@ -30,6 +30,8 @@ import com.google.gson.FormattingStyle;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.Strictness;
+import com.google.gson.util.StringEscapeUtil;
+
 import java.io.Closeable;
 import java.io.Flushable;
 import java.io.IOException;
@ -166,39 +168,6 @@ public class JsonWriter implements Closeable, Flushable {
  private static final Pattern VALID_JSON_NUMBER_PATTERN =
      Pattern.compile("-?(?:0|[1-9][0-9]*)(?:\\.[0-9]+)?(?:[eE][-+]?[0-9]+)?");

-  /*
-   * From RFC 8259, "All Unicode characters may be placed within the
-   * quotation marks except for the characters that must be escaped:
-   * quotation mark, reverse solidus, and the control characters
-   * (U+0000 through U+001F)."
-   *
-   * We also escape '\u2028' and '\u2029', which JavaScript interprets as
-   * newline characters. This prevents eval() from failing with a syntax
-   * error. http://code.google.com/p/google-gson/issues/detail?id=341
-   */
-  private static final String[] REPLACEMENT_CHARS;
-  private static final String[] HTML_SAFE_REPLACEMENT_CHARS;
-
-  static {
-    REPLACEMENT_CHARS = new String[128];
-    for (int i = 0; i <= 0x1f; i++) {
-      REPLACEMENT_CHARS[i] = String.format("\\u%04x", i);
-    }
-    REPLACEMENT_CHARS['"'] = "\\\"";
-    REPLACEMENT_CHARS['\\'] = "\\\\";
-    REPLACEMENT_CHARS['\t'] = "\\t";
-    REPLACEMENT_CHARS['\b'] = "\\b";
-    REPLACEMENT_CHARS['\n'] = "\\n";
-    REPLACEMENT_CHARS['\r'] = "\\r";
-    REPLACEMENT_CHARS['\f'] = "\\f";
-    HTML_SAFE_REPLACEMENT_CHARS = REPLACEMENT_CHARS.clone();
-    HTML_SAFE_REPLACEMENT_CHARS['<'] = "\\u003c";
-    HTML_SAFE_REPLACEMENT_CHARS['>'] = "\\u003e";
-    HTML_SAFE_REPLACEMENT_CHARS['&'] = "\\u0026";
-    HTML_SAFE_REPLACEMENT_CHARS['='] = "\\u003d";
-    HTML_SAFE_REPLACEMENT_CHARS['\''] = "\\u0027";
-  }
-
  /** The JSON output destination */
  private final Writer out;

@ -794,23 +763,13 @@ public class JsonWriter implements Closeable, Flushable {
  }

  private void string(String value) throws IOException {
-    String[] replacements = htmlSafe ? HTML_SAFE_REPLACEMENT_CHARS : REPLACEMENT_CHARS;
    out.write('\"');
    int last = 0;
    int length = value.length();
    for (int i = 0; i < length; i++) {
      char c = value.charAt(i);
-      String replacement;
-      if (c < 128) {
-        replacement = replacements[c];
-        if (replacement == null) {
-          continue;
-        }
-      } else if (c == '\u2028') {
-        replacement = "\\u2028";
-      } else if (c == '\u2029') {
-        replacement = "\\u2029";
-      } else {
+      String replacement = htmlSafe ? StringEscapeUtil.getHtmlSafeReplacement(c) : StringEscapeUtil.getReplacement(c);
+      if (replacement == null) {
        continue;
      }
      if (last < i) {
--- a/gson/src/main/java/com/google/gson/util/StringEscapeUtil.java
+++ b/gson/src/main/java/com/google/gson/util/StringEscapeUtil.java
@ -0,0 +1,80 @@
+package com.google.gson.util;
+
+/**
+ * Utilities methods for escaping strings, extracted from gsons JsonWriter.
+ * @author JFronny
+ */
+public class StringEscapeUtil {
+  private StringEscapeUtil() {}
+
+  /*
+   * From RFC 8259, "All Unicode characters may be placed within the
+   * quotation marks except for the characters that must be escaped:
+   * quotation mark, reverse solidus, and the control characters
+   * (U+0000 through U+001F)."
+   *
+   * We also escape '\u2028' and '\u2029', which JavaScript interprets as
+   * newline characters. This prevents eval() from failing with a syntax
+   * error. http://code.google.com/p/google-gson/issues/detail?id=341
+   */
+  private static final String[] REPLACEMENT_CHARS;
+  private static final String[] HTML_SAFE_REPLACEMENT_CHARS;
+
+  static {
+    REPLACEMENT_CHARS = new String[128];
+    for (int i = 0; i <= 0x1f; i++) {
+      REPLACEMENT_CHARS[i] = String.format("\\u%04x", i);
+    }
+    REPLACEMENT_CHARS['"'] = "\\\"";
+    REPLACEMENT_CHARS['\\'] = "\\\\";
+    REPLACEMENT_CHARS['\t'] = "\\t";
+    REPLACEMENT_CHARS['\b'] = "\\b";
+    REPLACEMENT_CHARS['\n'] = "\\n";
+    REPLACEMENT_CHARS['\r'] = "\\r";
+    REPLACEMENT_CHARS['\f'] = "\\f";
+    REPLACEMENT_CHARS['\0'] = "\\0";
+    HTML_SAFE_REPLACEMENT_CHARS = REPLACEMENT_CHARS.clone();
+    HTML_SAFE_REPLACEMENT_CHARS['<'] = "\\u003c";
+    HTML_SAFE_REPLACEMENT_CHARS['>'] = "\\u003e";
+    HTML_SAFE_REPLACEMENT_CHARS['&'] = "\\u0026";
+    HTML_SAFE_REPLACEMENT_CHARS['='] = "\\u003d";
+    HTML_SAFE_REPLACEMENT_CHARS['\''] = "\\u0027";
+  }
+
+  private static String getReplacement(char c, String[] replacements) {
+    String replacement;
+    if (c < 128) {
+      replacement = replacements[c];
+      if (replacement == null) {
+        return null;
+      }
+    } else if (c == '\u2028') {
+      replacement = "\\u2028";
+    } else if (c == '\u2029') {
+      replacement = "\\u2029";
+    } else {
+      return null;
+    }
+    return replacement;
+  }
+
+  /**
+   * Returns the replacement for the character, or null if the character does not need to be escaped.
+   * @param c the character to escape
+   * @return the replacement for the character, or null if the character does not need to be escaped
+   * @see #getHtmlSafeReplacement(char)
+   */
+  public static String getReplacement(char c) {
+    return getReplacement(c, REPLACEMENT_CHARS);
+  }
+
+  /**
+   * Returns the replacement for the character, or null if the character does not need to be escaped.
+   * @param c the character to escape
+   * @return the replacement for the character, or null if the character does not need to be escaped
+   * @see #getReplacement(char)
+   */
+  public static String getHtmlSafeReplacement(char c) {
+    return getReplacement(c, HTML_SAFE_REPLACEMENT_CHARS);
+  }
+}
--- a/gson/src/test/java/com/google/gson/ToNumberPolicyTest.java
+++ b/gson/src/test/java/com/google/gson/ToNumberPolicyTest.java
@ -40,7 +40,7 @@ public class ToNumberPolicyTest {
    assertThat(e)
        .hasMessageThat()
        .isEqualTo(
-            "JSON forbids NaN and infinities: Infinity at line 1 column 6 (char '\0') path $\n"
+            "JSON forbids NaN and infinities: Infinity at line 1 column 6 (char '\\0') path $\n"
                + "See https://github.com/google/gson/blob/main/Troubleshooting.md#malformed-json");

    assertThrows(
@ -133,7 +133,7 @@ public class ToNumberPolicyTest {
    assertThat(e)
        .hasMessageThat()
        .isEqualTo(
-            "Expected a double but was NULL at line 1 column 5 (char '\0') path $\n"
+            "Expected a double but was NULL at line 1 column 5 (char '\\0') path $\n"
                + "See https://github.com/google/gson/blob/main/Troubleshooting.md#adapter-not-null-safe");

    e =
@ -143,7 +143,7 @@ public class ToNumberPolicyTest {
    assertThat(e)
        .hasMessageThat()
        .isEqualTo(
-            "Expected a string but was NULL at line 1 column 5 (char '\0') path $\n"
+            "Expected a string but was NULL at line 1 column 5 (char '\\0') path $\n"
                + "See https://github.com/google/gson/blob/main/Troubleshooting.md#adapter-not-null-safe");

    e =
@ -153,7 +153,7 @@ public class ToNumberPolicyTest {
    assertThat(e)
        .hasMessageThat()
        .isEqualTo(
-            "Expected a string but was NULL at line 1 column 5 (char '\0') path $\n"
+            "Expected a string but was NULL at line 1 column 5 (char '\\0') path $\n"
                + "See https://github.com/google/gson/blob/main/Troubleshooting.md#adapter-not-null-safe");

    e =
@ -163,7 +163,7 @@ public class ToNumberPolicyTest {
    assertThat(e)
        .hasMessageThat()
        .isEqualTo(
-            "Expected a string but was NULL at line 1 column 5 (char '\0') path $\n"
+            "Expected a string but was NULL at line 1 column 5 (char '\\0') path $\n"
                + "See https://github.com/google/gson/blob/main/Troubleshooting.md#adapter-not-null-safe");
  }

--- a/gson/src/test/java/com/google/gson/functional/PrimitiveTest.java
+++ b/gson/src/test/java/com/google/gson/functional/PrimitiveTest.java
@ -97,7 +97,7 @@ public class PrimitiveTest {
        .hasMessageThat()
        .isEqualTo(
            "java.lang.NumberFormatException: Expected an int but was 2147483648"
-                + " at line 1 column 11 (char '\0') path $");
+                + " at line 1 column 11 (char '\\0') path $");
  }

  @Test
@ -140,7 +140,7 @@ public class PrimitiveTest {
        .hasMessageThat()
        .isEqualTo(
            "java.lang.NumberFormatException: Expected an int but was 2147483648"
-                + " at line 1 column 11 (char '\0') path $");
+                + " at line 1 column 11 (char '\\0') path $");
  }

  @Test
@ -915,7 +915,7 @@ public class PrimitiveTest {
    assertThat(e)
        .hasCauseThat()
        .hasMessageThat()
-        .isEqualTo("Expected an int but was -122.08e-213 at line 1 column 13 (char '\0') path $");
+        .isEqualTo("Expected an int but was -122.08e-213 at line 1 column 13 (char '\\0') path $");
  }

  @Test
@ -926,7 +926,7 @@ public class PrimitiveTest {
    assertThat(e)
        .hasCauseThat()
        .hasMessageThat()
-        .isEqualTo("Expected an int but was " + number + " at line 1 column 57 (char '\0') path $");
+        .isEqualTo("Expected an int but was " + number + " at line 1 column 57 (char '\\0') path $");
  }

  @Test
@ -937,7 +937,7 @@ public class PrimitiveTest {
    assertThat(e)
        .hasCauseThat()
        .hasMessageThat()
-        .isEqualTo("Expected a long but was " + number + " at line 1 column 57 (char '\0') path $");
+        .isEqualTo("Expected a long but was " + number + " at line 1 column 57 (char '\\0') path $");
  }

  @Test
--- a/gson/src/test/java/com/google/gson/stream/JsonReaderTest.java
+++ b/gson/src/test/java/com/google/gson/stream/JsonReaderTest.java
@ -1175,27 +1175,27 @@ public final class JsonReaderTest {
      fail();
    } catch (IllegalStateException expected) {
      assertUnexpectedStructureError(
-          expected, "a string", "END_OBJECT", "line 1 column 11 (char '\0') path $.a");
+          expected, "a string", "END_OBJECT", "line 1 column 11 (char '\\0') path $.a");
    }
    try {
      reader.nextName();
      fail();
    } catch (IllegalStateException expected) {
-      assertUnexpectedStructureError(expected, "a name", "END_OBJECT", "line 1 column 11 (char '\0') path $.a");
+      assertUnexpectedStructureError(expected, "a name", "END_OBJECT", "line 1 column 11 (char '\\0') path $.a");
    }
    try {
      reader.beginArray();
      fail();
    } catch (IllegalStateException expected) {
      assertUnexpectedStructureError(
-          expected, "BEGIN_ARRAY", "END_OBJECT", "line 1 column 11 (char '\0') path $.a");
+          expected, "BEGIN_ARRAY", "END_OBJECT", "line 1 column 11 (char '\\0') path $.a");
    }
    try {
      reader.endArray();
      fail();
    } catch (IllegalStateException expected) {
      assertUnexpectedStructureError(
-          expected, "END_ARRAY", "END_OBJECT", "line 1 column 11 (char '\0') path $.a");
+          expected, "END_ARRAY", "END_OBJECT", "line 1 column 11 (char '\\0') path $.a");
    }
    reader.endObject();
    assertThat(reader.peek()).isEqualTo(JsonToken.END_DOCUMENT);
@ -1623,7 +1623,7 @@ public final class JsonReaderTest {
      reader.nextNull();
      fail();
    } catch (IllegalStateException expected) {
-      assertThat(expected).hasMessageThat().startsWith("Expected null but was END_ARRAY at line 1 column 8 (char '\0') path $[1]");
+      assertThat(expected).hasMessageThat().startsWith("Expected null but was END_ARRAY at line 1 column 8 (char '\\0') path $[1]");
    }

    reader = new JsonReader(reader("[,]"));
@ -2109,7 +2109,7 @@ public final class JsonReaderTest {
      assertThat(expected)
          .hasMessageThat()
          .isEqualTo(
-              "Unterminated object at x at line 1 column 16 (char '\0') path $.a\n"
+              "Unterminated object at x at line 1 column 16 (char '\\0') path $.a\n"
                  + "See https://github.com/google/gson/blob/main/Troubleshooting.md#malformed-json");
    }
  }
@ -2241,7 +2241,7 @@ public final class JsonReaderTest {
      assertThat(expected)
          .hasMessageThat()
          .isEqualTo(
-              "Expected name at line 1 column 11 (char '\0') path $.a\n"
+              "Expected name at line 1 column 11 (char '\\0') path $.a\n"
                  + "See https://github.com/google/gson/blob/main/Troubleshooting.md#malformed-json");
    }
  }
@ -2260,7 +2260,7 @@ public final class JsonReaderTest {
      assertThat(expected)
          .hasMessageThat()
          .isEqualTo(
-              "Expected name at line 1 column 11 (char '\0') path $.a\n"
+              "Expected name at line 1 column 11 (char '\\0') path $.a\n"
                  + "See https://github.com/google/gson/blob/main/Troubleshooting.md#malformed-json");
    }
  }
--- a/gson/src/test/java/com/google/gson/stream/JsonWriterTest.java
+++ b/gson/src/test/java/com/google/gson/stream/JsonWriterTest.java
@ -698,7 +698,7 @@ public final class JsonWriterTest {
                + "\"}\","
                + "\"[\","
                + "\"]\","
-                + "\"\\u0000\","
+                + "\"\\0\","
                + "\"\\u0019\"]");
  }