Support Export Statements - WIP

src/Language/JavaScript/Parser/AST.hs

@@ -74,6 +74,7 @@ data JSStatement
     | JSVariable !JSAnnot !(JSCommaList JSExpression) !JSSemi -- ^var|const, decl, autosemi
     | JSWhile !JSAnnot !JSAnnot !JSExpression !JSAnnot !JSStatement -- ^while,lb,expr,rb,stmt
     | JSWith !JSAnnot !JSAnnot !JSExpression !JSAnnot !JSStatement !JSSemi -- ^with,lb,expr,rb,stmt list
+    | JSExport !JSAnnot !(Maybe JSAnnot) !JSStatement !JSSemi -- ^export
     deriving (Data, Eq, Show, Typeable)
 
 data JSExpression
@@ -271,6 +272,10 @@ instance ShowStripped JSStatement where
     ss (JSReturn _ (Just me) s) = "JSReturn " ++ ss me ++ " " ++ ss s
     ss (JSReturn _ Nothing s) = "JSReturn " ++ ss s
     ss (JSSwitch _ _lp x _rp _lb x2 _rb _) = "JSSwitch (" ++ ss x ++ ") " ++ ss x2
+    ss (JSExport _ df x1 _) = "JSExport " ++ exportDefault df ++ "(" ++ ss x1 ++ ")"
+      where
+        exportDefault (Just _) = "default "
+        exportDefault Nothing = ""
     ss (JSThrow _ x _) = "JSThrow (" ++ ss x ++ ")"
     ss (JSTry _ xt1 xtc xtf) = "JSTry (" ++ ss xt1 ++ "," ++ ss xtc ++ "," ++ ss xtf ++ ")"
     ss (JSVariable _ xs _as) = "JSVariable " ++ ss xs

src/Language/JavaScript/Parser/Lexer.x

@@ -566,6 +566,7 @@ keywordNames =
     , ( "export",   FutureToken )
     , ( "extends",  FutureToken )
 
+    , ( "export",   ExportToken )
     , ( "import",   FutureToken )
     , ( "super",    FutureToken )
 

src/Language/JavaScript/Parser/Token.hs

@@ -88,6 +88,7 @@ data Token
     | VoidToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | WhileToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     | WithToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
+    | ExportToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     -- Future reserved words
     | FutureToken { tokenSpan :: !TokenPosn, tokenLiteral :: !String, tokenComment :: ![CommentAnnotation]  }
     -- Needed, not sure what they are though.

src/Language/JavaScript/Pretty/Printer.hs

@@ -102,6 +102,10 @@ instance RenderJS JSAnnot where
     (|>) pacc JSNoAnnot = pacc
     (|>) pacc JSAnnotSpace = pacc |> " "
 
+instance RenderJS (Maybe JSAnnot) where
+    (|>) pacc (Just e) = pacc |> e
+    (|>) pacc Nothing  = pacc
+
 instance RenderJS String where
     (|>) (PosAccum (r,c) bb) s = PosAccum (r',c') (bb <> str s)
       where
@@ -233,6 +237,7 @@ instance RenderJS JSStatement where
     (|>) pacc (JSMethodCall e lp a rp s)                   = pacc |> e |> lp |> "(" |> a |> rp |> ")" |> s
     (|>) pacc (JSReturn annot me s)                        = pacc |> annot |> "return" |> me |> s
     (|>) pacc (JSSwitch annot alp x arp alb x2 arb s)      = pacc |> annot |> "switch" |> alp |> "(" |> x |> arp |> ")" |> alb |> "{" |> x2 |> arb |> "}" |> s
+    (|>) pacc (JSExport annot df x1 s)                     = pacc |> annot |> "export" |> df |> "{" |> x1 |> "}" |> s
     (|>) pacc (JSThrow annot x s)                          = pacc |> annot |> "throw" |> x |> s
     (|>) pacc (JSTry annot tb tcs tf)                      = pacc |> annot |> "try" |> tb |> tcs |> tf
     (|>) pacc (JSVariable annot xs s)                      = pacc |> annot |> "var" |> xs |> s
@@ -287,4 +292,3 @@ instance RenderJS JSVarInitializer where
     (|>) pacc JSVarInitNone   = pacc
 
 -- EOF
-

src/Language/JavaScript/Process/Minify.hs

@@ -60,6 +60,7 @@ fixStmt a s (JSMethodCall e _ args _ _) = JSMethodCall (fix a e) emptyAnnot (fix
 fixStmt a s (JSReturn _ me _) = JSReturn a (fixSpace me) s
 fixStmt a s (JSSwitch _ _ e _ _ sps _ _) = JSSwitch a emptyAnnot (fixEmpty e) emptyAnnot emptyAnnot (fixSwitchParts sps) emptyAnnot s
 fixStmt a s (JSThrow _ e _) = JSThrow a (fixSpace e) s
+fixStmt a s (JSExport _ df x1 _) = JSExport a (fixSpace df) (fixEmpty x1) s -- unsure what I'm doing here
 fixStmt a _ (JSTry _ b tc tf) = JSTry a (fixEmpty b) (map fixEmpty tc) (fixEmpty tf)
 fixStmt a s (JSVariable _ ss _) = JSVariable a (fixVarList ss) s
 fixStmt a s (JSWhile _ _ e _ st) = JSWhile a emptyAnnot (fixEmpty e) emptyAnnot (fixStmt a s st)

test/Test/Language/Javascript/StatementParser.hs

@@ -26,6 +26,27 @@ testStatementParser = describe "Parse statements:" $ do
     it "if" $
         testStmt "if (1) {}"    `shouldBe` "Right (JSAstStatement (JSIf (JSDecimal '1') (JSStatementBlock [])))"
 
+    it "export" $ do
+        testStmt "export a;"                      `shouldBe` "Right (JSAstStatement (JSExport (JSIdentifier 'a',JSSemicolon)))"
+        testStmt "export var a = 1;"              `shouldBe` "Right (JSAstStatement (JSExport (JSVariable (JSVarInitExpression (JSIdentifier 'a') [JSDecimal '1']))))"
+        testStmt "export function () {};"         `shouldBe` "Right (JSAstStatement (JSExport (JSFunctionExpression '' () (JSBlock [])),JSSemicolon)))"
+        testStmt "export {};"                     `shouldBe` "Right (JSAstStatement (JSExport (JSStatementBlock [])))"
+        testStmt "export default function () {};" `shouldBe` "Right (JSAstStatement (JSExport Default (JSFunctionExpression '' () (JSBlock [])),JSSemicolon)))"
+        testStmt "export default var a = 1;"      `shouldBe` "Right (JSAstStatement (JSExport Default (JSVariable (JSVarInitExpression (JSIdentifier 'a') [JSDecimal '1']))))"
+        -- Unsure about handling all these cases taken from the specs
+        -- export { variable1 as name1, variable2 as name2, …, nameN };
+        -- export let name1, name2, …, nameN; // also var, const
+        -- export let name1 = …, name2 = …, …, nameN; // also var, const
+        -- export class ClassName {...}
+        -- export default expression;
+        -- export default function name1(…) { … } // also class, function*
+        -- export { name1 as default, … };
+
+        -- export * from …;
+        -- export { name1, name2, …, nameN } from …;
+        -- export { import1 as name1, import2 as name2, …, nameN } from …;
+        -- export { default } from …;
+
     it "if/else" $ do
         testStmt "if (1) {} else {}"    `shouldBe` "Right (JSAstStatement (JSIfElse (JSDecimal '1') (JSStatementBlock []) (JSStatementBlock [])))"
         testStmt "if (1) x=1; else {}"  `shouldBe` "Right (JSAstStatement (JSIfElse (JSDecimal '1') (JSOpAssign ('=',JSIdentifier 'x',JSDecimal '1'),JSSemicolon) (JSStatementBlock [])))"
@@ -101,4 +122,3 @@ testStatementParser = describe "Parse statements:" $ do
 
 testStmt :: String -> String
 testStmt str = showStrippedMaybe (parseUsing parseStatement str "src")
-