erikd · erikd · Feb 19, 2019 · Sep 6, 2018
diff --git a/src/Language/JavaScript/Parser/AST.hs b/src/Language/JavaScript/Parser/AST.hs
@@ -25,6 +25,12 @@ module Language.JavaScript.Parser.AST
 
     -- Modules
     , JSModuleItem (..)
+    , JSImportDeclaration (..)
+    , JSImportClause (..)
+    , JSFromClause (..)
+    , JSImportNameSpace (..)
+    , JSImportsNamed (..)
+    , JSImportSpecifier (..)
     , JSExportDeclaration (..)
     , JSExportLocalSpecifier (..)
 
@@ -57,11 +63,46 @@ data JSAST
 -- Shift AST
 -- https://github.com/shapesecurity/shift-spec/blob/83498b92c436180cc0e2115b225a68c08f43c53e/spec.idl#L229-L234
 data JSModuleItem
-    -- = JSImportDeclaration
-    = JSModuleExportDeclaration !JSAnnot !JSExportDeclaration -- ^export,decl
+    = JSModuleImportDeclaration !JSAnnot !JSImportDeclaration -- ^import,decl
+    | JSModuleExportDeclaration !JSAnnot !JSExportDeclaration -- ^export,decl
     | JSModuleStatementListItem !JSStatement
     deriving (Data, Eq, Show, Typeable)
 
+data JSImportDeclaration
+    = JSImportDeclaration !JSImportClause !JSFromClause !JSSemi -- ^imports, module, semi
+    -- | JSImportDeclarationBare -- ^ module, semi
+    deriving (Data, Eq, Show, Typeable)
+
+data JSImportClause
+    = JSImportClauseDefault !JSIdent -- ^default
+    | JSImportClauseNameSpace !JSImportNameSpace -- ^namespace
+    | JSImportClauseNamed !JSImportsNamed -- ^named imports
+    | JSImportClauseDefaultNameSpace !JSIdent !JSAnnot !JSImportNameSpace -- ^default, comma, namespace
+    | JSImportClauseDefaultNamed !JSIdent !JSAnnot !JSImportsNamed -- ^default, comma, named imports
+    deriving (Data, Eq, Show, Typeable)
+
+data JSFromClause
+    = JSFromClause !JSAnnot !JSAnnot !String -- ^ from, string literal, string literal contents
+    deriving (Data, Eq, Show, Typeable)
+
+-- | Import namespace, e.g. '* as whatever'
+data JSImportNameSpace
+    = JSImportNameSpace !JSBinOp !JSBinOp !JSIdent -- ^ *, as, ident
+    deriving (Data, Eq, Show, Typeable)
+
+-- | Named imports, e.g. '{ foo, bar, baz as quux }'
+data JSImportsNamed
+    = JSImportsNamed !JSAnnot !(JSCommaList JSImportSpecifier) !JSAnnot -- ^lb, specifiers, rb
+    deriving (Data, Eq, Show, Typeable)
+
+-- |
+-- Note that this data type is separate from ExportSpecifier because the
+-- grammar is slightly different (e.g. in handling of reserved words).
+data JSImportSpecifier
+    = JSImportSpecifier !JSIdent -- ^ident
+    | JSImportSpecifierAs !JSIdent !JSBinOp !JSIdent -- ^ident, as, ident
+    deriving (Data, Eq, Show, Typeable)
+
 data JSExportDeclaration
     -- = JSExportAllFrom
     -- | JSExportFrom
@@ -338,8 +379,32 @@ instance ShowStripped JSExpression where
 
 instance ShowStripped JSModuleItem where
     ss (JSModuleExportDeclaration _ x1) = "JSModuleExportDeclaration (" ++ ss x1 ++ ")"
+    ss (JSModuleImportDeclaration _ x1) = "JSModuleImportDeclaration (" ++ ss x1 ++ ")"
     ss (JSModuleStatementListItem x1) = "JSModuleStatementListItem (" ++ ss x1 ++ ")"
 
+instance ShowStripped JSImportDeclaration where
+    ss (JSImportDeclaration imp from _) = "JSImportDeclaration (" ++ ss imp ++ "," ++ ss from ++ ")"
+
+instance ShowStripped JSImportClause where
+    ss (JSImportClauseDefault x) = "JSImportClauseDefault (" ++ ss x ++ ")"
+    ss (JSImportClauseNameSpace x) = "JSImportClauseNameSpace (" ++ ss x ++ ")"
+    ss (JSImportClauseNamed x) = "JSImportClauseNameSpace (" ++ ss x ++ ")"
+    ss (JSImportClauseDefaultNameSpace x1 _ x2) = "JSImportClauseDefaultNameSpace (" ++ ss x1 ++ "," ++ ss x2 ++ ")"
+    ss (JSImportClauseDefaultNamed x1 _ x2) = "JSImportClauseDefaultNamed (" ++ ss x1 ++ "," ++ ss x2 ++ ")"
+
+instance ShowStripped JSFromClause where
+    ss (JSFromClause _ _ m) = "JSFromClause " ++ singleQuote m
+
+instance ShowStripped JSImportNameSpace where
+    ss (JSImportNameSpace _ _ x) = "JSImportNameSpace (" ++ ss x ++ ")"
+
+instance ShowStripped JSImportsNamed where
+    ss (JSImportsNamed _ xs _) = "JSImportsNamed (" ++ ss xs ++ ")"
+
+instance ShowStripped JSImportSpecifier where
+    ss (JSImportSpecifier x1) = "JSImportSpecifier (" ++ ss x1 ++ ")"
+    ss (JSImportSpecifierAs x1 _ x2) = "JSImportSpecifierAs (" ++ ss x1 ++ "," ++ ss x2 ++ ")"
+
 instance ShowStripped JSExportDeclaration where
     ss (JSExportLocals _ xs _ _) = "JSExportLocals (" ++ ss xs ++ ")"
     ss (JSExport x1 _) = "JSExport (" ++ ss x1 ++ ")"

diff --git a/src/Language/JavaScript/Parser/Grammar7.y b/src/Language/JavaScript/Parser/Grammar7.y
@@ -101,8 +101,10 @@ import qualified Language.JavaScript.Parser.AST as AST
      'finally'    { FinallyToken {} }
      'for'        { ForToken {} }
      'function'   { FunctionToken {} }
+     'from'       { FromToken {} }
      'get'        { GetToken {} }
      'if'         { IfToken {} }
+     'import'     { ImportToken {} }
      'in'         { InToken {} }
      'instanceof' { InstanceofToken {} }
      'let'        { LetToken {} }
@@ -312,6 +314,12 @@ Let : 'let' { mkJSAnnot $1 }
 Const :: { AST.JSAnnot }
 Const : 'const' { mkJSAnnot $1 }
 
+Import :: { AST.JSAnnot }
+Import : 'import' { mkJSAnnot $1 }
+
+From :: { AST.JSAnnot }
+From : 'from' { mkJSAnnot $1 }
+
 Export :: { AST.JSAnnot }
 Export : 'export' { mkJSAnnot $1 }
 
@@ -432,6 +440,7 @@ Identifier :: { AST.JSExpression }
 Identifier : 'ident' { AST.JSIdentifier (mkJSAnnot $1) (tokenLiteral $1) }
            | 'get'   { AST.JSIdentifier (mkJSAnnot $1) "get" }
            | 'set'   { AST.JSIdentifier (mkJSAnnot $1) "set" }
+           | 'from'  { AST.JSIdentifier (mkJSAnnot $1) "from" }
 
 -- TODO: make this include any reserved word too, including future ones
 IdentifierName :: { AST.JSExpression }
@@ -453,6 +462,7 @@ IdentifierName : Identifier {$1}
              | 'finally'    { AST.JSIdentifier (mkJSAnnot $1) "finally" }
              | 'for'        { AST.JSIdentifier (mkJSAnnot $1) "for" }
              | 'function'   { AST.JSIdentifier (mkJSAnnot $1) "function" }
+             | 'from'       { AST.JSIdentifier (mkJSAnnot $1) "from" }
              | 'get'        { AST.JSIdentifier (mkJSAnnot $1) "get" }
              | 'if'         { AST.JSIdentifier (mkJSAnnot $1) "if" }
              | 'in'         { AST.JSIdentifier (mkJSAnnot $1) "in" }
@@ -1183,11 +1193,53 @@ ModuleItemList : ModuleItem                  { [$1]         {- 'ModuleItemList1'
 --        ExportDeclaration
 --        StatementListItem
 ModuleItem :: { AST.JSModuleItem }
-ModuleItem : Export ExportDeclaration
+ModuleItem : Import ImportDeclaration
+                    { AST.JSModuleImportDeclaration $1 $2   {- 'ModuleItem1' -} }
+           | Export ExportDeclaration
                     { AST.JSModuleExportDeclaration $1 $2   {- 'ModuleItem1' -} }
            | StatementListItem
                     { AST.JSModuleStatementListItem $1      {- 'ModuleItem2' -} }
 
+ImportDeclaration :: { AST.JSImportDeclaration }
+ImportDeclaration : ImportClause FromClause AutoSemi
+                          { AST.JSImportDeclaration $1 $2 $3 }
+
+ImportClause :: { AST.JSImportClause }
+ImportClause : IdentifierName
+                     { AST.JSImportClauseDefault (identName $1) }
+             | NameSpaceImport
+                     { AST.JSImportClauseNameSpace $1 }
+             | NamedImports
+                     { AST.JSImportClauseNamed $1 }
+             | IdentifierName ',' NameSpaceImport
+                     { AST.JSImportClauseDefaultNameSpace (identName $1) (mkJSAnnot $2) $3 }
+             | IdentifierName ',' NamedImports
+                     { AST.JSImportClauseDefaultNamed (identName $1) (mkJSAnnot $2) $3 }
+
+FromClause :: { AST.JSFromClause }
+FromClause : From 'string'
+                  { AST.JSFromClause $1 (mkJSAnnot $2) (tokenLiteral $2) }
+
+NameSpaceImport :: { AST.JSImportNameSpace }
+NameSpaceImport : Mul As IdentifierName
+                        { AST.JSImportNameSpace $1 $2 (identName $3) }
+
+NamedImports :: { AST.JSImportsNamed }
+NamedImports : LBrace ImportsList RBrace
+                      { AST.JSImportsNamed $1 $2 $3 }
+
+ImportsList :: { AST.JSCommaList AST.JSImportSpecifier }
+ImportsList : ImportSpecifier
+                    { AST.JSLOne $1 }
+            | ImportsList Comma ImportSpecifier
+                    { AST.JSLCons $1 $2 $3 }
+
+ImportSpecifier :: { AST.JSImportSpecifier }
+ImportSpecifier : IdentifierName
+                    { AST.JSImportSpecifier (identName $1) }
+                | IdentifierName As IdentifierName
+                    { AST.JSImportSpecifierAs (identName $1) $2 (identName $3) }
+
 -- ExportDeclaration :                                                        See 15.2.3
 -- [ ]    export * FromClause ;
 -- [ ]    export ExportClause FromClause ;

diff --git a/src/Language/JavaScript/Parser/Lexer.x b/src/Language/JavaScript/Parser/Lexer.x
@@ -525,7 +525,9 @@ keywordNames =
     , ( "finally", FinallyToken )
     , ( "for", ForToken )
     , ( "function", FunctionToken )
+    , ( "from", FromToken )
     , ( "if", IfToken )
+    , ( "import", ImportToken )
     , ( "in", InToken )
     , ( "instanceof", InstanceofToken )
     , ( "let", LetToken )
@@ -566,8 +568,6 @@ keywordNames =
     -- ( "const",   FutureToken ) **** an actual token, used in productions
     -- enum                    **** an actual token, used in productions
     , ( "extends",  FutureToken )
-
-    , ( "import",   FutureToken )
     , ( "super",    FutureToken )
 
 

diff --git a/src/Language/JavaScript/Parser/Token.hs b/src/Language/JavaScript/Parser/Token.hs
@@ -73,6 +73,7 @@ data Token
     | FinallyToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | ForToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | FunctionToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
+    | FromToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | IfToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | InToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | InstanceofToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
@@ -88,6 +89,7 @@ data Token
     | VarToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | VoidToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | WhileToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
+    | ImportToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | WithToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | ExportToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     -- Future reserved words

diff --git a/src/Language/JavaScript/Pretty/Printer.hs b/src/Language/JavaScript/Pretty/Printer.hs
@@ -248,6 +248,7 @@ instance RenderJS [JSModuleItem] where
     (|>) = foldl' (|>)
 
 instance RenderJS JSModuleItem where
+    (|>) pacc (JSModuleImportDeclaration annot decl) = pacc |> annot |> "import" |> decl
     (|>) pacc (JSModuleExportDeclaration annot decl) = pacc |> annot |> "export" |> decl
     (|>) pacc (JSModuleStatementListItem s) = pacc |> s
 
@@ -274,6 +275,29 @@ instance RenderJS JSArrayElement where
 instance RenderJS [JSArrayElement] where
     (|>) = foldl' (|>)
 
+instance RenderJS JSImportDeclaration where
+    (|>) pacc (JSImportDeclaration imp from annot) = pacc |> imp |> from |> annot
+
+instance RenderJS JSImportClause where
+    (|>) pacc (JSImportClauseDefault x) = pacc |> x
+    (|>) pacc (JSImportClauseNameSpace x) = pacc |> x
+    (|>) pacc (JSImportClauseNamed x) = pacc |> x
+    (|>) pacc (JSImportClauseDefaultNameSpace x1 annot x2) = pacc |> x1 |> annot |> "," |> x2
+    (|>) pacc (JSImportClauseDefaultNamed x1 annot x2) = pacc |> x1 |> annot |> "," |> x2
+
+instance RenderJS JSFromClause where
+    (|>) pacc (JSFromClause from annot m) = pacc |> from |> "from" |> annot |> m
+
+instance RenderJS JSImportNameSpace where
+    (|>) pacc (JSImportNameSpace star as x) = pacc |> star |> as |> x
+
+instance RenderJS JSImportsNamed where
+    (|>) pacc (JSImportsNamed lb xs rb) = pacc |> lb |> "{" |> xs |> rb |> "}"
+
+instance RenderJS JSImportSpecifier where
+    (|>) pacc (JSImportSpecifier x1) = pacc |> x1
+    (|>) pacc (JSImportSpecifierAs x1 as x2) = pacc |> x1 |> as |> x2
+
 instance RenderJS JSExportDeclaration where
     (|>) pacc (JSExport x1 s) = pacc |> " " |> x1 |> s
     (|>) pacc (JSExportLocals alb JSLNil arb semi) = pacc |> alb |> "{" |> arb |> "}" |> semi

diff --git a/src/Language/JavaScript/Process/Minify.hs b/src/Language/JavaScript/Process/Minify.hs
@@ -268,9 +268,40 @@ instance MinifyJS JSAssignOp where
     fix a (JSBwOrAssign   _) = JSBwOrAssign a
 
 instance MinifyJS JSModuleItem where
+    fix _ (JSModuleImportDeclaration _ x1) = JSModuleImportDeclaration emptyAnnot (fixEmpty x1)
     fix _ (JSModuleExportDeclaration _ x1) = JSModuleExportDeclaration emptyAnnot (fixEmpty x1)
     fix a (JSModuleStatementListItem s) = JSModuleStatementListItem (fixStmt a noSemi s)
 
+instance MinifyJS JSImportDeclaration where
+    fix _ (JSImportDeclaration imps from _) = JSImportDeclaration (fixEmpty imps) (fix annot from) noSemi
+        where
+        annot = case imps of
+                    JSImportClauseDefault {} -> spaceAnnot
+                    JSImportClauseNameSpace {} -> spaceAnnot
+                    JSImportClauseNamed {} -> emptyAnnot
+                    JSImportClauseDefaultNameSpace {} -> spaceAnnot
+                    JSImportClauseDefaultNamed {} -> emptyAnnot
+
+instance MinifyJS JSImportClause where
+    fix _ (JSImportClauseDefault n) = JSImportClauseDefault (fixSpace n)
+    fix _ (JSImportClauseNameSpace ns) = JSImportClauseNameSpace (fixSpace ns)
+    fix _ (JSImportClauseNamed named) = JSImportClauseNamed (fixEmpty named)
+    fix _ (JSImportClauseDefaultNameSpace def _ ns) = JSImportClauseDefaultNameSpace (fixSpace def) emptyAnnot (fixEmpty ns)
+    fix _ (JSImportClauseDefaultNamed def _ ns) = JSImportClauseDefaultNamed (fixSpace def) emptyAnnot (fixEmpty ns)
+
+instance MinifyJS JSFromClause where
+    fix a (JSFromClause _ _ m) = JSFromClause a emptyAnnot m
+
+instance MinifyJS JSImportNameSpace where
+    fix a (JSImportNameSpace _ _ ident) = JSImportNameSpace (JSBinOpTimes a) (JSBinOpAs spaceAnnot) (fixSpace ident)
+
+instance MinifyJS JSImportsNamed where
+    fix _ (JSImportsNamed _ imps _) = JSImportsNamed emptyAnnot (fixEmpty imps) emptyAnnot 
+
+instance MinifyJS JSImportSpecifier where
+    fix _ (JSImportSpecifier x1) = JSImportSpecifier (fixEmpty x1)
+    fix _ (JSImportSpecifierAs x1 as x2) = JSImportSpecifierAs (fixEmpty x1) (fixSpace as) (fixSpace x2)
+
 instance MinifyJS JSExportDeclaration where
     fix _ (JSExportLocals _ x1 _ _) = JSExportLocals emptyAnnot (fixEmpty x1) emptyAnnot noSemi
     fix _ (JSExport x1 _) = JSExport (fixStmt emptyAnnot noSemi x1) noSemi

diff --git a/test/Test/Language/Javascript/Minify.hs b/test/Test/Language/Javascript/Minify.hs
@@ -255,7 +255,14 @@ testMinifyProg = describe "Minify programs:" $ do
         minifyProg " try { } catch (a) {} finally {} ; try { } catch ( b ) { } ; " `shouldBe` "try{}catch(a){}finally{}try{}catch(b){}"
 
 testMinifyModule :: Spec
-testMinifyModule = describe "Minify modules:" $
+testMinifyModule = describe "Minify modules:" $ do
+    it "import" $ do
+        minifyModule "import  def  from 'mod' ; " `shouldBe` "import def from'mod'"
+        minifyModule "import   *  as  foo  from   \"mod\"  ; " `shouldBe` "import * as foo from\"mod\""
+        minifyModule "import  def, * as foo  from   \"mod\"  ; " `shouldBe` "import def,* as foo from\"mod\""
+        minifyModule "import  { baz,  bar as   foo }  from   \"mod\"  ; " `shouldBe` "import{baz,bar as foo}from\"mod\""
+        minifyModule "import  def, { baz,  bar as   foo }  from   \"mod\"  ; " `shouldBe` "import def,{baz,bar as foo}from\"mod\""
+
     it "export" $ do
         minifyModule " export { } ; " `shouldBe` "export{}"
         minifyModule " export { a } ; " `shouldBe` "export{a}"

diff --git a/test/Test/Language/Javascript/ModuleParser.hs b/test/Test/Language/Javascript/ModuleParser.hs
@@ -8,7 +8,30 @@ import Language.JavaScript.Parser
 
 
 testModuleParser :: Spec
-testModuleParser = describe "Parse modules:" $
+testModuleParser = describe "Parse modules:" $ do
+    it "import" $ do
+        -- Not yet supported
+        -- test "import 'a';"            `shouldBe` ""
+
+        test "import def from 'mod';"
+            `shouldBe`
+            "Right (JSAstModule [JSModuleImportDeclaration (JSImportDeclaration (JSImportClauseDefault (JSIdentifier 'def'),JSFromClause ''mod''))])"
+        test "import def from \"mod\";"
+            `shouldBe`
+            "Right (JSAstModule [JSModuleImportDeclaration (JSImportDeclaration (JSImportClauseDefault (JSIdentifier 'def'),JSFromClause '\"mod\"'))])"
+        test "import * as thing from 'mod';"
+            `shouldBe`
+            "Right (JSAstModule [JSModuleImportDeclaration (JSImportDeclaration (JSImportClauseNameSpace (JSImportNameSpace (JSIdentifier 'thing')),JSFromClause ''mod''))])"
+        test "import { foo, bar, baz as quux } from 'mod';"
+            `shouldBe`
+            "Right (JSAstModule [JSModuleImportDeclaration (JSImportDeclaration (JSImportClauseNameSpace (JSImportsNamed ((JSImportSpecifier (JSIdentifier 'foo'),JSImportSpecifier (JSIdentifier 'bar'),JSImportSpecifierAs (JSIdentifier 'baz',JSIdentifier 'quux')))),JSFromClause ''mod''))])"
+        test "import def, * as thing from 'mod';"
+            `shouldBe`
+            "Right (JSAstModule [JSModuleImportDeclaration (JSImportDeclaration (JSImportClauseDefaultNameSpace (JSIdentifier 'def',JSImportNameSpace (JSIdentifier 'thing')),JSFromClause ''mod''))])"
+        test "import def, { foo, bar, baz as quux } from 'mod';"
+            `shouldBe`
+            "Right (JSAstModule [JSModuleImportDeclaration (JSImportDeclaration (JSImportClauseDefaultNamed (JSIdentifier 'def',JSImportsNamed ((JSImportSpecifier (JSIdentifier 'foo'),JSImportSpecifier (JSIdentifier 'bar'),JSImportSpecifierAs (JSIdentifier 'baz',JSIdentifier 'quux')))),JSFromClause ''mod''))])"
+
     it "export" $ do
         test "export {}"
             `shouldBe`
@@ -26,5 +49,6 @@ testModuleParser = describe "Parse modules:" $
             `shouldBe`
             "Right (JSAstModule [JSModuleExportDeclaration (JSExportLocals ((JSExportLocalSpecifierAs (JSIdentifier 'a',JSIdentifier 'b'))))])"
 
+
 test :: String -> String
 test str = showStrippedMaybe (parseModule str "src")
diff --git a/test/Test/Language/Javascript/RoundTrip.hs b/test/Test/Language/Javascript/RoundTrip.hs
@@ -101,6 +101,13 @@ testRoundTrip = describe "Roundtrip:" $ do
         testRT "var x=1;let y=2;"
 
     it "module" $ do
+        testRTModule "import  def  from 'mod'"
+        testRTModule "import  def  from   \"mod\";"
+        testRTModule "import   * as foo  from   \"mod\"  ; "
+        testRTModule "import  def, * as foo  from   \"mod\"  ; "
+        testRTModule "import  { baz,  bar as   foo }  from   \"mod\"  ; "
+        testRTModule "import  def, { baz,  bar as   foo }  from   \"mod\"  ; "
+
         testRTModule "export   {};"
         testRTModule "  export {}   ;  "
         testRTModule "export {  a  ,  b  ,  c  };"