Merge branch 'main' into js/shared-dataflow

javascript/ql/lib/semmle/javascript/internal/CachedStages.qll

@@ -158,7 +158,7 @@ module Stages {
       or
       exists(DataFlow::ssaDefinitionNode(_))
       or
-      any(DataFlow::Node node).hasLocationInfo(_, _, _, _, _)
+      exists(any(DataFlow::Node node).getLocation())
       or
       exists(any(DataFlow::Node node).toString())
       or

javascript/ql/lib/semmle/javascript/internal/Locations.qll

@@ -0,0 +1,171 @@
+/** Provides classes for working with locations and program elements that have locations. */
+
+import javascript
+
+// Should _not_ be cached, as that would require the data flow stage to be evaluated
+// in order to evaluate the AST stage. Ideally, we would cache each injector separately,
+// but that's not possible. Instead, we cache all predicates that need the injectors
+// to be tuple numbered.
+newtype TLocation =
+  TDbLocation(@location loc) or
+  TSynthLocation(string filepath, int startline, int startcolumn, int endline, int endcolumn) {
+    any(SsaDefinition def).hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) and
+    // avoid overlap with existing DB locations
+    not exists(File f |
+      locations_default(_, f, startline, startcolumn, endline, endcolumn) and
+      f.getAbsolutePath() = filepath
+    )
+  }
+
+/**
+ * A location as given by a file, a start line, a start column,
+ * an end line, and an end column.
+ *
+ * For more information about locations see [Locations](https://codeql.github.com/docs/writing-codeql-queries/providing-locations-in-codeql-queries/).
+ */
+abstract class LocationImpl extends TLocation {
+  /** Gets the file for this location. */
+  abstract File getFile();
+
+  /** Gets the 1-based line number (inclusive) where this location starts. */
+  abstract int getStartLine();
+
+  /** Gets the 1-based column number (inclusive) where this location starts. */
+  abstract int getStartColumn();
+
+  /** Gets the 1-based line number (inclusive) where this location ends. */
+  abstract int getEndLine();
+
+  /** Gets the 1-based column number (inclusive) where this location ends. */
+  abstract int getEndColumn();
+
+  /** Gets the number of lines covered by this location. */
+  int getNumLines() { result = this.getEndLine() - this.getStartLine() + 1 }
+
+  /** Holds if this location starts before location `that`. */
+  pragma[inline]
+  predicate startsBefore(Location that) {
+    exists(string f, int sl1, int sc1, int sl2, int sc2 |
+      this.hasLocationInfo(f, sl1, sc1, _, _) and
+      that.hasLocationInfo(f, sl2, sc2, _, _)
+    |
+      sl1 < sl2
+      or
+      sl1 = sl2 and sc1 < sc2
+    )
+  }
+
+  /** Holds if this location ends after location `that`. */
+  pragma[inline]
+  predicate endsAfter(Location that) {
+    exists(string f, int el1, int ec1, int el2, int ec2 |
+      this.hasLocationInfo(f, _, _, el1, ec1) and
+      that.hasLocationInfo(f, _, _, el2, ec2)
+    |
+      el1 > el2
+      or
+      el1 = el2 and ec1 > ec2
+    )
+  }
+
+  /**
+   * Holds if this location contains location `that`, meaning that it starts
+   * before and ends after it.
+   */
+  predicate contains(Location that) { this.startsBefore(that) and this.endsAfter(that) }
+
+  /** Holds if this location is empty. */
+  predicate isEmpty() { exists(int l, int c | this.hasLocationInfo(_, l, c, l, c - 1)) }
+
+  /** Gets a textual representation of this element. */
+  string toString() { result = this.getFile().getBaseName() + ":" + this.getStartLine().toString() }
+
+  /**
+   * Holds if this element is at the specified location.
+   * The location spans column `startcolumn` of line `startline` to
+   * column `endcolumn` of line `endline` in file `filepath`.
+   * For more information, see
+   * [Locations](https://codeql.github.com/docs/writing-codeql-queries/providing-locations-in-codeql-queries/).
+   */
+  abstract predicate hasLocationInfo(
+    string filepath, int startline, int startcolumn, int endline, int endcolumn
+  );
+}
+
+class DbLocationImpl extends LocationImpl instanceof DbLocation {
+  override File getFile() { result = DbLocation.super.getFile() }
+
+  override int getStartLine() { result = DbLocation.super.getStartLine() }
+
+  override int getStartColumn() { result = DbLocation.super.getStartColumn() }
+
+  override int getEndLine() { result = DbLocation.super.getEndLine() }
+
+  override int getEndColumn() { result = DbLocation.super.getEndColumn() }
+
+  override predicate hasLocationInfo(
+    string filepath, int startline, int startcolumn, int endline, int endcolumn
+  ) {
+    DbLocation.super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
+  }
+}
+
+class SynthLocationImpl extends LocationImpl, TSynthLocation {
+  override File getFile() { synthLocationInfo(this, result.getAbsolutePath(), _, _, _, _) }
+
+  override int getStartLine() { synthLocationInfo(this, _, result, _, _, _) }
+
+  override int getStartColumn() { synthLocationInfo(this, _, _, result, _, _) }
+
+  override int getEndLine() { synthLocationInfo(this, _, _, _, result, _) }
+
+  override int getEndColumn() { synthLocationInfo(this, _, _, _, _, result) }
+
+  override predicate hasLocationInfo(
+    string filepath, int startline, int startcolumn, int endline, int endcolumn
+  ) {
+    synthLocationInfo(this, filepath, startline, startcolumn, endline, endcolumn)
+  }
+}
+
+cached
+private module Cached {
+  cached
+  DbLocation getLocatableLocation(@locatable l) {
+    exists(@location loc |
+      hasLocation(l, loc) or
+      xmllocations(l, loc) or
+      json_locations(l, loc) or
+      yaml_locations(l, loc)
+    |
+      result = TDbLocation(loc)
+    )
+  }
+
+  cached
+  predicate dbLocationInfo(
+    DbLocation l, File f, int startline, int startcolumn, int endline, int endcolumn
+  ) {
+    exists(@location loc |
+      l = TDbLocation(loc) and
+      locations_default(loc, f, startline, startcolumn, endline, endcolumn)
+    )
+  }
+}
+
+import Cached
+
+cached
+private module CachedInDataFlowStage {
+  private import semmle.javascript.internal.CachedStages
+
+  cached
+  predicate synthLocationInfo(
+    SynthLocationImpl l, string filepath, int startline, int startcolumn, int endline, int endcolumn
+  ) {
+    Stages::DataFlowStage::ref() and
+    l = TSynthLocation(filepath, startline, startcolumn, endline, endcolumn)
+  }
+}
+
+private import CachedInDataFlowStage