Merge pull request #20302 from asgerf/js/simpler-locations

JS: Remove synthetic locations

Author: asgerf

javascript/ql/lib/semmle/javascript/AST.qll

@@ -31,7 +31,7 @@ class AstNode extends @ast_node, NodeInStmtContainer {
 
   /** Gets the first token belonging to this element. */
   Token getFirstToken() {
-    exists(DbLocation l1, DbLocation l2, string filepath, int startline, int startcolumn |
+    exists(Location l1, Location l2, string filepath, int startline, int startcolumn |
       l1 = this.getLocation() and
       l2 = result.getLocation() and
       l1.hasLocationInfo(filepath, startline, startcolumn, _, _) and
@@ -41,7 +41,7 @@ class AstNode extends @ast_node, NodeInStmtContainer {
 
   /** Gets the last token belonging to this element. */
   Token getLastToken() {
-    exists(DbLocation l1, DbLocation l2, string filepath, int endline, int endcolumn |
+    exists(Location l1, Location l2, string filepath, int endline, int endcolumn |
       l1 = this.getLocation() and
       l2 = result.getLocation() and
       l1.hasLocationInfo(filepath, _, _, endline, endcolumn) and

javascript/ql/lib/semmle/javascript/Files.qll

@@ -3,7 +3,6 @@
 import javascript
 private import NodeModuleResolutionImpl
 private import codeql.util.FileSystem
-private import internal.Locations
 
 private module FsInput implements InputSig {
   abstract class ContainerBase extends @container {
@@ -99,7 +98,7 @@ class File extends Container, Impl::File {
    *
    * Note that files have special locations starting and ending at line zero, column zero.
    */
-  DbLocation getLocation() { result = getLocatableLocation(this) }
+  Location getLocation() { hasLocation(this, result) }
 
   /** Gets the number of lines in this file. */
   int getNumberOfLines() { result = sum(int loc | numlines(this, loc, _, _) | loc) }

javascript/ql/lib/semmle/javascript/JSON.qll

@@ -3,7 +3,6 @@
  */
 
 import javascript
-private import semmle.javascript.internal.Locations
 
 /**
  * A JSON-encoded value, which may be a primitive value, an array or an object.
@@ -33,7 +32,7 @@ class JsonValue extends @json_value, Locatable {
   override string toString() { json(this, _, _, _, result) }
 
   /** Gets the JSON file containing this value. */
-  File getJsonFile() { result = getLocatableLocation(this).getFile() }
+  File getJsonFile() { exists(Location loc | json_locations(this, loc) and result = loc.getFile()) }
 
   /** If this is an object, gets the value of property `name`. */
   JsonValue getPropValue(string name) { json_properties(this, name, result) }

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

@@ -1,7 +1,6 @@
 /** Provides classes for working with locations and program elements that have locations. */
 
 import javascript
-private import internal.Locations
 
 /**
  * A location as given by a file, a start line, a start column,
@@ -11,31 +10,31 @@ private import internal.Locations
  *
  * For more information about locations see [Locations](https://codeql.github.com/docs/writing-codeql-queries/providing-locations-in-codeql-queries/).
  */
-class DbLocation extends TDbLocation {
+final class Location extends @location_default {
   /** Gets the file for this location. */
-  File getFile() { dbLocationInfo(this, result, _, _, _, _) }
+  File getFile() { locations_default(this, result, _, _, _, _) }
 
   /** Gets the 1-based line number (inclusive) where this location starts. */
-  int getStartLine() { dbLocationInfo(this, _, result, _, _, _) }
+  int getStartLine() { locations_default(this, _, result, _, _, _) }
 
   /** Gets the 1-based column number (inclusive) where this location starts. */
-  int getStartColumn() { dbLocationInfo(this, _, _, result, _, _) }
+  int getStartColumn() { locations_default(this, _, _, result, _, _) }
 
   /** Gets the 1-based line number (inclusive) where this location ends. */
-  int getEndLine() { dbLocationInfo(this, _, _, _, result, _) }
+  int getEndLine() { locations_default(this, _, _, _, result, _) }
 
   /** Gets the 1-based column number (inclusive) where this location ends. */
-  int getEndColumn() { dbLocationInfo(this, _, _, _, _, result) }
+  int getEndColumn() { locations_default(this, _, _, _, _, result) }
 
   /** 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(DbLocation that) {
-    exists(File f, int sl1, int sc1, int sl2, int sc2 |
-      dbLocationInfo(this, f, sl1, sc1, _, _) and
-      dbLocationInfo(that, f, sl2, sc2, _, _)
+  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
@@ -45,10 +44,10 @@ class DbLocation extends TDbLocation {
 
   /** Holds if this location ends after location `that`. */
   pragma[inline]
-  predicate endsAfter(DbLocation that) {
-    exists(File f, int el1, int ec1, int el2, int ec2 |
-      dbLocationInfo(this, f, _, _, el1, ec1) and
-      dbLocationInfo(that, f, _, _, el2, ec2)
+  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
@@ -60,10 +59,10 @@ class DbLocation extends TDbLocation {
    * Holds if this location contains location `that`, meaning that it starts
    * before and ends after it.
    */
-  predicate contains(DbLocation that) { this.startsBefore(that) and this.endsAfter(that) }
+  predicate contains(Location that) { this.startsBefore(that) and this.endsAfter(that) }
 
   /** Holds if this location is empty. */
-  predicate isEmpty() { exists(int l, int c | dbLocationInfo(this, _, l, c, l, c - 1)) }
+  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() }
@@ -79,21 +78,27 @@ class DbLocation extends TDbLocation {
     string filepath, int startline, int startcolumn, int endline, int endcolumn
   ) {
     exists(File f |
-      dbLocationInfo(this, f, startline, startcolumn, endline, endcolumn) and
+      locations_default(this, f, startline, startcolumn, endline, endcolumn) and
       filepath = f.getAbsolutePath()
     )
   }
 }
 
-final class Location = LocationImpl;
+cached
+private Location getLocatableLocation(@locatable l) {
+  hasLocation(l, result) or
+  xmllocations(l, result) or
+  json_locations(l, result) or
+  yaml_locations(l, result)
+}
 
 /** A program element with a location. */
 class Locatable extends @locatable {
   /** Gets the file this program element comes from. */
   File getFile() { result = this.getLocation().getFile() }
 
   /** Gets this element's location. */
-  final DbLocation getLocation() { result = getLocatableLocation(this) }
+  final Location getLocation() { result = getLocatableLocation(this) }
 
   /**
    * Gets the line on which this element starts.
@@ -144,3 +149,8 @@ class Locatable extends @locatable {
    */
   string getAPrimaryQlClass() { result = "???" }
 }
+
+/**
+ * DEPRECATED. Use `Location` instead.
+ */
+deprecated class DbLocation = Location;

javascript/ql/lib/semmle/javascript/RestrictedLocations.qll

@@ -26,7 +26,7 @@ class FirstLineOf extends Locatable {
       then endcolumn = xc
       else
         endcolumn =
-          max(int c | any(DbLocation l).hasLocationInfo(filepath, startline, _, startline, c))
+          max(int c | any(Location l).hasLocationInfo(filepath, startline, _, startline, c))
     )
   }
 }

javascript/ql/lib/semmle/javascript/SSA.qll

@@ -108,8 +108,8 @@ private module Internal {
    */
   cached
   newtype TSsaDefinition =
-    TExplicitDef(ReachableBasicBlock bb, int i, VarDef d, SsaSourceVariable v) {
-      bb.defAt(i, v, d) and
+    TExplicitDef(ReachableBasicBlock bb, int i, VarDef d, SsaSourceVariable v, VarRef lhs) {
+      bb.defAt(i, v, d, lhs) and
       (
         liveAfterDef(bb, i, v) or
         v.isCaptured()
@@ -412,17 +412,22 @@ class SsaVariable extends TSsaDefinition {
   /** Gets a textual representation of this element. */
   string toString() { result = this.getDefinition().prettyPrintRef() }
 
+  /** Gets the location of this SSA variable. */
+  Location getLocation() { result = this.getDefinition().getLocation() }
+
   /**
+   * DEPRECATED. Use `getLocation().hasLocationInfo()` instead.
+   *
    * 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/).
    */
-  predicate hasLocationInfo(
+  deprecated predicate hasLocationInfo(
     string filepath, int startline, int startcolumn, int endline, int endcolumn
   ) {
-    this.getDefinition().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
+    this.getLocation().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
   }
 }
 
@@ -478,23 +483,22 @@ class SsaDefinition extends TSsaDefinition {
   string toString() { result = this.prettyPrintDef() }
 
   /**
+   * DEPRECATED. Use `getLocation().hasLocationInfo()` instead.
+   *
    * 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(
+  deprecated predicate hasLocationInfo(
     string filepath, int startline, int startcolumn, int endline, int endcolumn
-  );
+  ) {
+    this.getLocation().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
+  }
 
   /** Gets the location of this element. */
-  final Location getLocation() {
-    exists(string filepath, int startline, int startcolumn, int endline, int endcolumn |
-      this.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) and
-      result.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-    )
-  }
+  Location getLocation() { result = this.getBasicBlock().getLocation() }
 
   /** Gets the function or toplevel to which this definition belongs. */
   StmtContainer getContainer() { result = this.getBasicBlock().getContainer() }
@@ -505,36 +509,34 @@ class SsaDefinition extends TSsaDefinition {
  */
 class SsaExplicitDefinition extends SsaDefinition, TExplicitDef {
   override predicate definesAt(ReachableBasicBlock bb, int i, SsaSourceVariable v) {
-    this = TExplicitDef(bb, i, _, v)
+    this = TExplicitDef(bb, i, _, v, _)
   }
 
   /** This SSA definition corresponds to the definition of `v` at `def`. */
-  predicate defines(VarDef def, SsaSourceVariable v) { this = TExplicitDef(_, _, def, v) }
+  predicate defines(VarDef def, SsaSourceVariable v) { this = TExplicitDef(_, _, def, v, _) }
 
   /** Gets the variable definition wrapped by this SSA definition. */
-  VarDef getDef() { this = TExplicitDef(_, _, result, _) }
+  VarDef getDef() { this = TExplicitDef(_, _, result, _, _) }
+
+  /** Gets the variable reference appearing on the left-hand side of this assignment. */
+  VarRef getLhs() { this = TExplicitDef(_, _, _, _, result) }
 
   /** Gets the basic block to which this definition belongs. */
   override ReachableBasicBlock getBasicBlock() { this.definesAt(result, _, _) }
 
-  override SsaSourceVariable getSourceVariable() { this = TExplicitDef(_, _, _, result) }
+  override SsaSourceVariable getSourceVariable() { this = TExplicitDef(_, _, _, result, _) }
 
   override VarDef getAContributingVarDef() { result = this.getDef() }
 
   override string prettyPrintRef() {
-    exists(int l, int c | this.hasLocationInfo(_, l, c, _, _) | result = "def@" + l + ":" + c)
+    exists(int l, int c | this.getLocation().hasLocationInfo(_, l, c, _, _) |
+      result = "def@" + l + ":" + c
+    )
   }
 
   override string prettyPrintDef() { result = this.getDef().toString() }
 
-  override predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    exists(Location loc |
-      pragma[only_bind_into](loc) = pragma[only_bind_into](this.getDef()).getLocation() and
-      loc.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-    )
-  }
+  override Location getLocation() { result = this.getLhs().getLocation() }
 
   /**
    * Gets the data flow node representing the incoming value assigned at this definition,
@@ -557,21 +559,10 @@ abstract class SsaImplicitDefinition extends SsaDefinition {
   abstract string getKind();
 
   override string prettyPrintRef() {
-    exists(int l, int c | this.hasLocationInfo(_, l, c, _, _) |
+    exists(int l, int c | this.getLocation().hasLocationInfo(_, l, c, _, _) |
       result = this.getKind() + "@" + l + ":" + c
     )
   }
-
-  override predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    endline = startline and
-    endcolumn = startcolumn and
-    exists(Location loc |
-      pragma[only_bind_into](loc) = pragma[only_bind_into](this.getBasicBlock()).getLocation() and
-      loc.hasLocationInfo(filepath, startline, startcolumn, _, _)
-    )
-  }
 }
 
 /**
@@ -617,16 +608,6 @@ class SsaVariableCapture extends SsaImplicitDefinition, TCapture {
   override string getKind() { result = "capture" }
 
   override string prettyPrintDef() { result = "capture variable " + this.getSourceVariable() }
-
-  override predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    exists(ReachableBasicBlock bb, int i | this.definesAt(bb, i, _) |
-      bb.getNode(i)
-          .getLocation()
-          .hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-    )
-  }
 }
 
 /**
@@ -747,13 +728,7 @@ class SsaRefinementNode extends SsaPseudoDefinition, TRefinement {
       this.getSourceVariable() + " = refine[" + this.getGuard() + "](" + this.ppInputs() + ")"
   }
 
-  override predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    this.getGuard()
-        .getLocation()
-        .hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
+  override Location getLocation() { result = this.getGuard().getLocation() }
 }
 
 module Ssa {

javascript/ql/lib/semmle/javascript/Variables.qll

@@ -353,9 +353,9 @@ class LocalVariable extends Variable {
    * If the variable has one or more declarations, the location of the first declaration is used.
    * If the variable has no declaration, the entry point of its declaring container is used.
    */
-  DbLocation getLocation() {
+  Location getLocation() {
     result =
-      min(DbLocation loc |
+      min(Location loc |
         loc = this.getADeclaration().getLocation()
       |
         loc order by loc.getStartLine(), loc.getStartColumn()

javascript/ql/lib/semmle/javascript/XML.qll

@@ -3,13 +3,12 @@
  */
 
 import semmle.files.FileSystem
-private import semmle.javascript.internal.Locations
 private import codeql.xml.Xml
 
-private module Input implements InputSig<File, DbLocation> {
+private module Input implements InputSig<File, Location> {
   class XmlLocatableBase = @xmllocatable or @xmlnamespaceable;
 
-  predicate xmllocations_(XmlLocatableBase e, DbLocation loc) { loc = getLocatableLocation(e) }
+  predicate xmllocations_(XmlLocatableBase e, Location loc) { xmllocations(e, loc) }
 
   class XmlParentBase = @xmlparent;
 
@@ -67,4 +66,4 @@ private module Input implements InputSig<File, DbLocation> {
   }
 }
 
-import Make<File, DbLocation, Input>
+import Make<File, Location, Input>

javascript/ql/lib/semmle/javascript/YAML.qll

@@ -9,8 +9,6 @@ import javascript
 private import codeql.yaml.Yaml as LibYaml
 
 private module YamlSig implements LibYaml::InputSig {
-  class Location = DbLocation;
-
   class LocatableBase extends @yaml_locatable, Locatable { }
 
   import javascript