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resources/app/node_modules/peggy/lib/grammar-location.js

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+"use strict";
+
+/**
+ * When used as a grammarSource, allows grammars embedded in larger files to
+ * specify their offset.  The start location is the first character in the
+ * grammar.  The first line is often moved to the right by some number of
+ * columns, but subsequent lines all start at the first column.
+ */
+class GrammarLocation {
+  /**
+   * Create an instance.
+   *
+   * @param {any} source The original grammarSource.  Should be a string or
+   *   have a toString() method.
+   * @param {import("./peg").Location} start The starting offset for the
+   *   grammar in the larger file.
+   */
+  constructor(source, start) {
+    this.source = source;
+    this.start = start;
+  }
+
+  /**
+   * Coerce to a string.
+   *
+   * @returns {string} The source, stringified.
+   */
+  toString() {
+    return String(this.source);
+  }
+
+  /**
+   * Return a new Location offset from the given location by the start of the
+   * grammar.
+   *
+   * @param {import("./peg").Location} loc The location as if the start of the
+   *   grammar was the start of the file.
+   * @returns {import("./peg").Location} The offset location.
+   */
+  offset(loc) {
+    return {
+      line: loc.line + this.start.line - 1,
+      column: (loc.line === 1)
+        ? loc.column + this.start.column - 1
+        : loc.column,
+      offset: loc.offset + this.start.offset,
+    };
+  }
+
+  /**
+   * If the range has a grammarSource that is a GrammarLocation, offset the
+   * start of that range by the GrammarLocation.
+   *
+   * @param {import("./peg").LocationRange} range The range to extract from.
+   * @returns {import("./peg").Location} The offset start if possible, or the
+   *   original start.
+   */
+  static offsetStart(range) {
+    if (range.source && (typeof range.source.offset === "function")) {
+      return range.source.offset(range.start);
+    }
+    return range.start;
+  }
+
+  /**
+   * If the range has a grammarSource that is a GrammarLocation, offset the
+   * end of that range by the GrammarLocation.
+   *
+   * @param {import("./peg").LocationRange} range The range to extract from.
+   * @returns {import("./peg").Location} The offset end if possible, or the
+   *   original end.
+   */
+  static offsetEnd(range) {
+    if (range.source && (typeof range.source.offset === "function")) {
+      return range.source.offset(range.end);
+    }
+    return range.end;
+  }
+}
+
+module.exports = GrammarLocation;