word(String)

Author: fluentfuture

dot-parse/README.md

@@ -316,6 +316,10 @@ Stream<String> jsonStringsFrom(Reader input) {
 }
 ```
 
+Note that JSON supports Unicode escape. But we don't need to care because we are just splitting by calling
+`.source()` after finding the split point. The parser translating a unicode escape correctly or not
+is irrelevant.
+
 ## Example — Mini Search Language
 
 Imagine you are building your own search engine, and you want to allow users to search by search terms.

dot-parse/src/main/java/com/google/common/labs/parse/Parser.java

@@ -161,6 +161,15 @@ public static Parser<String> chars(int n) {
     };
   }
 
+  /**
+   * {@code word("equal")} matches "equal" but not "equals".
+   *
+   * @since 9.4
+   */
+  public static Parser<String> word(String word) {
+    return string(word).notImmediatelyFollowedBy(CharPredicate.WORD, "[a-zA-Z0-9_]");
+  }
+
   /**
    * One or more regex {@code \w+} characters.
    *
@@ -242,7 +251,7 @@ public static Parser<String> quotedStringWithEscapes(
    *
    * will return the emoji {@code 😀}.
    *
-   * <p>You can also use it together with {@link #quotedStringWithEscapes}:
+   * <p>You can also compose it with {@link #quotedStringWithEscapes}:
    *
    * <pre>{@code
    * quotedStringWithEscapes('"', string("u").then(codePoint()).map(Character::toString));

dot-parse/src/test/java/com/google/common/labs/parse/ParserTest.java

@@ -83,6 +83,40 @@ public void string_cannotBeEmpty() {
     assertThrows(IllegalArgumentException.class, () -> string(""));
   }
 
+  @Test
+  public void word_success() {
+    assertThat(word("foo").parse("foo")).isEqualTo("foo");
+  }
+
+  @Test
+  public void word_failIfFollowedByWordChar() {
+    assertThrows(ParseException.class, () -> word("foo").parse("foobar"));
+    assertThrows(ParseException.class, () -> word("foo").parse("foo_bar"));
+    assertThrows(ParseException.class, () -> word("foo").parse("foo1"));
+  }
+
+  @Test
+  public void word_successIfNotFollowedByWordChar() {
+    assertThat(word("foo").probe("foo?")).containsExactly("foo");
+    assertThat(word("foo").probe("foo-")).containsExactly("foo");
+  }
+
+  @Test
+  public void word_skipping_success() {
+    assertThat(word("foo").skipping(Character::isWhitespace).parseToStream("foo")).containsExactly("foo");
+    assertThat(word("foo").skipping(Character::isWhitespace).parseToStream("foo foo"))
+        .containsExactly("foo", "foo");
+    assertThat(word("foo").skipping(Character::isWhitespace).probe(" foo-foo")).containsExactly("foo");
+  }
+
+  @Test
+  public void word_skipping_failIfFollowedByWordChar() {
+    assertThrows(ParseException.class, () -> word("foo").parseSkipping(Character::isWhitespace, "foobar"));
+    assertThrows(ParseException.class, () -> word("foo").parseSkipping(Character::isWhitespace, "foo_bar"));
+    assertThrows(ParseException.class, () -> word("foo").parseSkipping(Character::isWhitespace, "foo1"));
+    assertThrows(ParseException.class, () -> word("foo").parseSkipping(Character::isWhitespace, " foo1"));
+  }
+
   @Test
   public void testNulls() {
     NullPointerTester tester =