JS: Overhaul import resolution

javascript/ql/examples/snippets/importfrom.ql

@@ -11,5 +11,5 @@
 import javascript
 
 from ImportDeclaration id
-where id.getImportedPath().getValue() = "react"
+where id.getImportedPathString() = "react"
 select id

javascript/ql/lib/definitions.qll

@@ -70,7 +70,7 @@ private predicate importLookup(AstNode path, Module target, string kind) {
   kind = "I" and
   (
     exists(Import i |
-      path = i.getImportedPath() and
+      path = i.getImportedPathExpr() and
       target = i.getImportedModule()
     )
     or

javascript/ql/lib/semmle/javascript/AMD.qll

@@ -61,8 +61,14 @@ class AmdModuleDefinition extends CallExpr instanceof AmdModuleDefinition::Range
     result = this.getArgument(1)
   }
 
+  /** DEPRECATED. Use `getDependencyExpr` instead. */
+  deprecated PathExpr getDependency(int i) { result = this.getDependencyExpr(i) }
+
+  /** DEPRECATED. Use `getADependencyExpr` instead. */
+  deprecated PathExpr getADependency() { result = this.getADependencyExpr() }
+
   /** Gets the `i`th dependency of this module definition. */
-  PathExpr getDependency(int i) {
+  Expr getDependencyExpr(int i) {
     exists(Expr expr |
       expr = this.getDependencies().getElement(i) and
       not isPseudoDependency(expr.getStringValue()) and
@@ -71,8 +77,8 @@ class AmdModuleDefinition extends CallExpr instanceof AmdModuleDefinition::Range
   }
 
   /** Gets a dependency of this module definition. */
-  PathExpr getADependency() {
-    result = this.getDependency(_) or
+  Expr getADependencyExpr() {
+    result = this.getDependencyExpr(_) or
     result = this.getARequireCall().getAnArgument()
   }
 
@@ -233,7 +239,7 @@ private class AmdDependencyPath extends PathExprCandidate {
 }
 
 /** A constant path element appearing in an AMD dependency expression. */
-private class ConstantAmdDependencyPathElement extends PathExpr, ConstantString {
+deprecated private class ConstantAmdDependencyPathElement extends PathExpr, ConstantString {
   ConstantAmdDependencyPathElement() { this = any(AmdDependencyPath amd).getAPart() }
 
   override string getValue() { result = this.getStringValue() }
@@ -261,11 +267,13 @@ private predicate amdModuleTopLevel(AmdModuleDefinition def, TopLevel tl) {
  * An AMD dependency, viewed as an import.
  */
 private class AmdDependencyImport extends Import {
-  AmdDependencyImport() { this = any(AmdModuleDefinition def).getADependency() }
+  AmdDependencyImport() { this = any(AmdModuleDefinition def).getADependencyExpr() }
 
-  override Module getEnclosingModule() { this = result.(AmdModule).getDefine().getADependency() }
+  override Module getEnclosingModule() {
+    this = result.(AmdModule).getDefine().getADependencyExpr()
+  }
 
-  override PathExpr getImportedPath() { result = this }
+  override Expr getImportedPathExpr() { result = this }
 
   /**
    * Gets a file that looks like it might be the target of this import.
@@ -274,7 +282,7 @@ private class AmdDependencyImport extends Import {
    * adding well-known JavaScript file extensions like `.js`.
    */
   private File guessTarget() {
-    exists(PathString imported, string abspath, string dirname, string basename |
+    exists(FilePath imported, string abspath, string dirname, string basename |
       this.targetCandidate(result, abspath, imported, dirname, basename)
     |
       abspath.regexpMatch(".*/\\Q" + imported + "\\E")
@@ -296,9 +304,9 @@ private class AmdDependencyImport extends Import {
    * `dirname` and `basename` to the dirname and basename (respectively) of `imported`.
    */
   private predicate targetCandidate(
-    File f, string abspath, PathString imported, string dirname, string basename
+    File f, string abspath, FilePath imported, string dirname, string basename
   ) {
-    imported = this.getImportedPath().getValue() and
+    imported = this.getImportedPathString() and
     f.getStem() = imported.getStem() and
     f.getAbsolutePath() = abspath and
     dirname = imported.getDirName() and

javascript/ql/lib/semmle/javascript/ES2015Modules.qll

@@ -92,13 +92,13 @@ private predicate hasDefaultExport(ES2015Module mod) {
 class ImportDeclaration extends Stmt, Import, @import_declaration {
   override ES2015Module getEnclosingModule() { result = this.getTopLevel() }
 
-  override PathExpr getImportedPath() { result = this.getChildExpr(-1) }
-
   /**
    * INTERNAL USE ONLY. DO NOT USE.
    */
   string getRawImportPath() { result = this.getChildExpr(-1).getStringValue() }
 
+  override Expr getImportedPathExpr() { result = this.getChildExpr(-1) }
+
   /**
    * Gets the object literal passed as part of the `with` (or `assert`) clause in this import declaration.
    *
@@ -155,7 +155,7 @@ class ImportDeclaration extends Stmt, Import, @import_declaration {
 }
 
 /** A literal path expression appearing in an `import` declaration. */
-private class LiteralImportPath extends PathExpr, ConstantString {
+deprecated private class LiteralImportPath extends PathExpr, ConstantString {
   LiteralImportPath() { exists(ImportDeclaration req | this = req.getChildExpr(-1)) }
 
   override string getValue() { result = this.getStringValue() }
@@ -736,7 +736,7 @@ abstract class ReExportDeclaration extends ExportDeclaration {
 }
 
 /** A literal path expression appearing in a re-export declaration. */
-private class LiteralReExportPath extends PathExpr, ConstantString {
+deprecated private class LiteralReExportPath extends PathExpr, ConstantString {
   LiteralReExportPath() { exists(ReExportDeclaration bred | this = bred.getImportedPath()) }
 
   override string getValue() { result = this.getStringValue() }

javascript/ql/lib/semmle/javascript/Expr.qll

@@ -2821,7 +2821,7 @@ class DynamicImportExpr extends @dynamic_import, Expr, Import {
     result = this.getSource().getFirstControlFlowNode()
   }
 
-  override PathExpr getImportedPath() { result = this.getSource() }
+  override Expr getImportedPathExpr() { result = this.getSource() }
 
   /**
    * Gets the second "argument" to the import expression, that is, the `Y` in `import(X, Y)`.
@@ -2852,7 +2852,7 @@ class DynamicImportExpr extends @dynamic_import, Expr, Import {
 }
 
 /** A literal path expression appearing in a dynamic import. */
-private class LiteralDynamicImportPath extends PathExpr, ConstantString {
+deprecated private class LiteralDynamicImportPath extends PathExpr, ConstantString {
   LiteralDynamicImportPath() {
     exists(DynamicImportExpr di | this.getParentExpr*() = di.getSource())
   }

javascript/ql/lib/semmle/javascript/HTML.qll

@@ -214,7 +214,7 @@ module HTML {
         result = path.regexpCapture("file://(/.*)", 1)
         or
         not path.regexpMatch("(\\w+:)?//.*") and
-        result = this.getSourcePath().(ScriptSrcPath).resolve(this.getSearchRoot()).toString()
+        result = ResolveScriptSrc::resolve(this.getSearchRoot(), this.getSourcePath()).toString()
       )
     }
 
@@ -274,10 +274,16 @@ module HTML {
     )
   }
 
+  private module ResolverConfig implements Folder::ResolveSig {
+    predicate shouldResolve(Container base, string path) { scriptSrc(path, base) }
+  }
+
+  private module ResolveScriptSrc = Folder::Resolve<ResolverConfig>;
+
   /**
    * A path string arising from the `src` attribute of a `script` tag.
    */
-  private class ScriptSrcPath extends PathString {
+  deprecated private class ScriptSrcPath extends PathString {
     ScriptSrcPath() { scriptSrc(this, _) }
 
     override Folder getARootFolder() { scriptSrc(this, result) }

javascript/ql/lib/semmle/javascript/Modules.qll

@@ -69,7 +69,7 @@ abstract class Module extends TopLevel {
    * This predicate is not part of the public API, it is only exposed to allow
    * overriding by subclasses.
    */
-  predicate searchRoot(PathExpr path, Folder searchRoot, int priority) {
+  deprecated predicate searchRoot(PathExpr path, Folder searchRoot, int priority) {
     path.getEnclosingModule() = this and
     priority = 0 and
     exists(string v | v = path.getValue() |
@@ -90,7 +90,7 @@ abstract class Module extends TopLevel {
    * resolves to a folder containing a main module (such as `index.js`), then
    * that file is the result.
    */
-  File resolve(PathExpr path) {
+  deprecated File resolve(PathExpr path) {
     path.getEnclosingModule() = this and
     (
       // handle the case where the import path is complete
@@ -123,8 +123,14 @@ abstract class Import extends AstNode {
   /** Gets the module in which this import appears. */
   abstract Module getEnclosingModule();
 
+  /** DEPRECATED. Use `getImportedPathExpr` instead. */
+  deprecated PathExpr getImportedPath() { result = this.getImportedPathExpr() }
+
   /** Gets the (unresolved) path that this import refers to. */
-  abstract PathExpr getImportedPath();
+  abstract Expr getImportedPathExpr();
+
+  /** Gets the imported path as a string. */
+  final string getImportedPathString() { result = this.getImportedPathExpr().getStringValue() }
 
   /**
    * Gets an externs module the path of this import resolves to.
@@ -133,7 +139,7 @@ abstract class Import extends AstNode {
    * path is assumed to be a possible target of the import.
    */
   Module resolveExternsImport() {
-    result.isExterns() and result.getName() = this.getImportedPath().getValue()
+    result.isExterns() and result.getName() = this.getImportedPathString()
   }
 
   /**
@@ -144,7 +150,7 @@ abstract class Import extends AstNode {
   /**
    * Gets the module the path of this import resolves to.
    */
-  File getTargetFile() { result = ImportPathResolver::resolveExpr(this.getImportedPath()) }
+  File getTargetFile() { result = ImportPathResolver::resolveExpr(this.getImportedPathExpr()) }
 
   /**
    * DEPRECATED. Use `getImportedModule()` instead.

javascript/ql/lib/semmle/javascript/NodeJS.qll

@@ -146,7 +146,7 @@ class NodeModule extends Module {
     )
   }
 
-  override predicate searchRoot(PathExpr path, Folder searchRoot, int priority) {
+  deprecated override predicate searchRoot(PathExpr path, Folder searchRoot, int priority) {
     path.getEnclosingModule() = this and
     exists(string pathval | pathval = path.getValue() |
       // paths starting with `./` or `../` are resolved relative to the importing
@@ -236,11 +236,6 @@ private class RequireVariable extends Variable {
   }
 }
 
-/**
- * Holds if module `m` is in file `f`.
- */
-private predicate moduleInFile(Module m, File f) { m.getFile() = f }
-
 private predicate isModuleModule(EarlyStageNode nd) {
   exists(ImportDeclaration imp | imp.getRawImportPath() = "module" |
     nd = TDestructuredModuleImportNode(imp)
@@ -328,24 +323,17 @@ private predicate isRequire(EarlyStageNode nd) {
 class Require extends CallExpr, Import {
   Require() { isRequire(TValueNode(this.getCallee())) }
 
-  override PathExpr getImportedPath() { result = this.getArgument(0) }
+  override Expr getImportedPathExpr() { result = this.getArgument(0) }
 
   override Module getEnclosingModule() { this = result.getAnImport() }
 
-  override Module resolveImportedPath() {
-    moduleInFile(result, this.load(min(int prio | moduleInFile(_, this.load(prio)))))
-    or
-    not moduleInFile(_, this.load(_)) and
-    result = Import.super.resolveImportedPath()
-  }
-
   /**
    * Gets the file that is imported by this `require`.
    *
    * The result can be a JavaScript file, a JSON file or a `.node` file.
    * Externs files are not treated differently from other files by this predicate.
    */
-  File getImportedFile() { result = this.load(min(int prio | exists(this.load(prio)))) }
+  deprecated File getImportedFile() { result = this.load(min(int prio | exists(this.load(prio)))) }
 
   /**
    * Gets the file that this `require` refers to (which may not be a JavaScript file),
@@ -402,8 +390,8 @@ class Require extends CallExpr, Import {
    * predicate `tryExtensions` that handles the repeated distinction between
    * `.js`, `.json` and `.node`.
    */
-  private File load(int priority) {
-    exists(int r | this.getEnclosingModule().searchRoot(this.getImportedPath(), _, r) |
+  deprecated private File load(int priority) {
+    exists(int r | this.getEnclosingModule().searchRoot(this.getImportedPathExpr(), _, r) |
       result = loadAsFile(this, r, priority - prioritiesPerCandidate() * r) or
       result =
         loadAsDirectory(this, r,
@@ -415,7 +403,7 @@ class Require extends CallExpr, Import {
 }
 
 /** An argument to `require` or `require.resolve`, considered as a path expression. */
-private class RequirePath extends PathExprCandidate {
+deprecated private class RequirePath extends PathExprCandidate {
   RequirePath() {
     this = any(Require req).getArgument(0)
     or
@@ -428,14 +416,14 @@ private class RequirePath extends PathExprCandidate {
 }
 
 /** A constant path element appearing in a call to `require` or `require.resolve`. */
-private class ConstantRequirePathElement extends PathExpr, ConstantString {
+deprecated private class ConstantRequirePathElement extends PathExpr, ConstantString {
   ConstantRequirePathElement() { this = any(RequirePath rp).getAPart() }
 
   override string getValue() { result = this.getStringValue() }
 }
 
 /** A `__dirname` path expression. */
-private class DirNamePath extends PathExpr, VarAccess {
+deprecated private class DirNamePath extends PathExpr, VarAccess {
   DirNamePath() {
     this.getName() = "__dirname" and
     this.getVariable().getScope() instanceof ModuleScope
@@ -445,7 +433,7 @@ private class DirNamePath extends PathExpr, VarAccess {
 }
 
 /** A `__filename` path expression. */
-private class FileNamePath extends PathExpr, VarAccess {
+deprecated private class FileNamePath extends PathExpr, VarAccess {
   FileNamePath() {
     this.getName() = "__filename" and
     this.getVariable().getScope() instanceof ModuleScope
@@ -458,7 +446,7 @@ private class FileNamePath extends PathExpr, VarAccess {
  * A path expression of the form `path.join(p, "...")` where
  * `p` is also a path expression.
  */
-private class JoinedPath extends PathExpr, @call_expr {
+deprecated private class JoinedPath extends PathExpr, @call_expr {
   JoinedPath() {
     exists(MethodCallExpr call | call = this |
       call.getReceiver().(VarAccess).getName() = "path" and