tools: move eslint from tools to tools/node_modules

This is required because we need to add the babel-eslint dependency
and it has to be able to resolve "eslint".
babel-eslint is required to support future ES features such as async
iterators and import.meta.

Refs: https://github.com/nodejs/node/pull/17755
PR-URL: https://github.com/nodejs/node/pull/17820
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

1 files changed, 77 insertions, 0 deletions

diff --git a/tools/node_modules/eslint/node_modules/vfile-location/index.js b/tools/node_modules/eslint/node_modules/vfile-location/index.js
new file mode 100644
index 0000000000..9263d2486a
--- /dev/null
+++ b/tools/node_modules/eslint/node_modules/vfile-location/index.js
@@ -0,0 +1,77 @@
+'use strict';
+
+/* Expose. */
+module.exports = factory;
+
+/* Factory. */
+function factory(file) {
+  var contents = indices(String(file));
+
+  return {
+    toPosition: offsetToPositionFactory(contents),
+    toOffset: positionToOffsetFactory(contents)
+  };
+}
+
+/* Factory to get the line and column-based `position` for
+ * `offset` in the bound indices. */
+function offsetToPositionFactory(indices) {
+  return offsetToPosition;
+
+  /* Get the line and column-based `position` for
+   * `offset` in the bound indices. */
+  function offsetToPosition(offset) {
+    var index = -1;
+    var length = indices.length;
+
+    if (offset < 0) {
+      return {};
+    }
+
+    while (++index < length) {
+      if (indices[index] > offset) {
+        return {
+          line: index + 1,
+          column: (offset - (indices[index - 1] || 0)) + 1,
+          offset: offset
+        };
+      }
+    }
+
+    return {};
+  }
+}
+
+/* Factory to get the `offset` for a line and column-based
+ * `position` in the bound indices. */
+function positionToOffsetFactory(indices) {
+  return positionToOffset;
+
+  /* Get the `offset` for a line and column-based
+   * `position` in the bound indices. */
+  function positionToOffset(position) {
+    var line = position && position.line;
+    var column = position && position.column;
+
+    if (!isNaN(line) && !isNaN(column) && line - 1 in indices) {
+      return ((indices[line - 2] || 0) + column - 1) || 0;
+    }
+
+    return -1;
+  }
+}
+
+/* Get indices of line-breaks in `value`. */
+function indices(value) {
+  var result = [];
+  var index = value.indexOf('\n');
+
+  while (index !== -1) {
+    result.push(index + 1);
+    index = value.indexOf('\n', index + 1);
+  }
+
+  result.push(value.length + 1);
+
+  return result;
+}