Merge pull request #1232 from github/json

Add a JSON Parser

.gitmodules

@@ -34,3 +34,6 @@
 [submodule "languages/python/vendor/tree-sitter-python"]
 	path = languages/python/vendor/tree-sitter-python
 	url = https://github.com/tree-sitter/tree-sitter-python.git
+[submodule "languages/json/vendor/tree-sitter-json"]
+	path = languages/json/vendor/tree-sitter-json
+	url = https://github.com/tree-sitter/tree-sitter-json

languages/json/Setup.hs

@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain

languages/json/json.cabal

@@ -0,0 +1,27 @@
+name:                json
+version:             0.1.0
+synopsis:            tree-sitter json language bindings
+description:         Please see README.md
+homepage:            https://github.com/github/semantic-diff#readme
+author:              semantic-code
+maintainer:          vera@github.com
+copyright:           2017 GitHub
+category:            Web
+build-type:          Simple
+-- extra-source-files:
+cabal-version:       >=1.10
+
+library
+  hs-source-dirs:      src
+  exposed-modules:     Text.Parser.TreeSitter.JSON
+  build-depends:       base >= 4.7 && < 5
+                     , haskell-tree-sitter
+  default-language:    Haskell2010
+  default-extensions:  FlexibleInstances, OverloadedStrings, NoImplicitPrelude, RecordWildCards
+  c-sources:           vendor/tree-sitter-json/src/parser.c
+  cc-options:          -std=c99 -Os
+
+
+source-repository head
+  type:     git
+  location: https://github.com/github/semantic-diff

languages/json/src/Text/Parser/TreeSitter/JSON.hs

@@ -0,0 +1,6 @@
+module Text.Parser.TreeSitter.JSON where
+
+import Foreign.Ptr
+import Text.Parser.TreeSitter
+
+foreign import ccall unsafe "vendor/tree-sitter-json/src/parser.c tree_sitter_json" tree_sitter_json :: Ptr Language

languages/json/vendor/tree-sitter-json

@@ -0,0 +1 @@
+Subproject commit 5c21eb6446ca3e0a49fe710fb948d8efb8a5b6da

semantic-diff.cabal

@@ -50,6 +50,8 @@ library
                      , Language.Markdown.Syntax
                      , Language.Go
                      , Language.Go.Syntax
+                     , Language.JSON.Grammar
+                     , Language.JSON.Syntax
                      , Language.Ruby
                      , Language.Ruby.Grammar
                      , Language.Ruby.Syntax
@@ -117,6 +119,7 @@ library
                      , ruby
                      , typescript
                      , python
+                     , json
   default-language:    Haskell2010
   default-extensions:  DeriveFunctor, DeriveFoldable, DeriveTraversable, DeriveGeneric, FlexibleContexts, FlexibleInstances, OverloadedStrings, NoImplicitPrelude, RecordWildCards, StrictData
   ghc-options:         -Wall -fno-warn-name-shadowing -O -j

src/Language.hs

@@ -14,6 +14,7 @@ data Language =
       C
     | Go
     | JavaScript
+    | JSON
     | Markdown
     | Python
     | Ruby
@@ -25,6 +26,7 @@ languageForType :: String -> Maybe Language
 languageForType mediaType = case mediaType of
     ".h" -> Just C
     ".c" -> Just C
+    ".json" -> Just JSON
     ".md" -> Just Markdown
     ".rb" -> Just Ruby
     ".go" -> Just Language.Go

src/Language/JSON/Grammar.hs

@@ -0,0 +1,10 @@
+{-# LANGUAGE TemplateHaskell #-}
+module Language.JSON.Grammar where
+
+import Language.Haskell.TH
+import Text.Parser.TreeSitter.Language
+import Text.Parser.TreeSitter.JSON
+
+-- | Statically-known rules corresponding to symbols in the grammar.
+-- v1 - bump this to regenerate
+mkSymbolDatatype (mkName "Grammar") tree_sitter_json

src/Language/JSON/Syntax.hs

@@ -0,0 +1,68 @@
+{-# LANGUAGE DataKinds, GADTs, RankNTypes, TypeOperators #-}
+module Language.JSON.Syntax
+  ( assignment
+  , Syntax
+  , Grammar
+  , Term)
+  where
+
+import qualified Data.Syntax as Syntax
+import qualified Data.Syntax.Literal as Literal
+import Data.Syntax.Assignment hiding (Assignment, Error)
+import qualified Data.Syntax.Assignment as Assignment
+import Language.JSON.Grammar as Grammar
+import qualified Term
+import Data.Record
+import Data.Union
+import GHC.Stack
+import Prologue hiding (Location)
+
+type Syntax =
+  [ Literal.Array
+  , Literal.Boolean
+  , Literal.Hash
+  , Literal.Float
+  , Literal.KeyValue
+  , Literal.Null
+  , Literal.String
+  , Literal.TextElement
+  , Syntax.Error
+  , []
+  ]
+
+type Term = Term.Term (Union Syntax) (Record Location)
+type Assignment = HasCallStack => Assignment.Assignment (AST Grammar) Grammar Term
+
+
+makeTerm :: (HasCallStack, f :< fs) => a -> f (Term.Term (Union fs) a) -> Term.Term (Union fs) a
+makeTerm a f = cofree (a :< inj f)
+
+parseError :: Assignment
+parseError = makeTerm <$> symbol ParseError <*> (Syntax.Error [] <$ source)
+
+assignment :: Assignment
+assignment = object <|> array <|> parseError
+
+value :: Assignment
+value = object <|> array <|> number <|> string <|> boolean <|> none <|> parseError
+
+object :: Assignment
+object = makeTerm <$> symbol Object <*> children (Literal.Hash <$> many pairs)
+  where pairs = makeTerm <$> symbol Pair <*> children (Literal.KeyValue <$> (number <|> string) <*> value)
+
+array :: Assignment
+array = makeTerm <$> symbol Array <*> children (Literal.Array <$> many value)
+
+number :: Assignment
+number = makeTerm <$> symbol Number <*> (Literal.Float <$> source)
+
+string :: Assignment
+string = makeTerm <$> symbol String <*> (Literal.TextElement <$> source)
+
+boolean :: Assignment
+boolean =  makeTerm <$> symbol Grammar.True  <*> (Literal.true <$ source)
+       <|> makeTerm <$> symbol Grammar.False <*> (Literal.false <$ source)
+
+none :: Assignment
+none = makeTerm <$> symbol Null <*> (Literal.Null <$ source)
+

src/Parser.hs

@@ -5,6 +5,7 @@ module Parser
 -- Syntax parsers
 , parserForLanguage
 -- À la carte parsers
+, jsonParser
 , markdownParser
 , pythonParser
 , rubyParser
@@ -21,6 +22,7 @@ import Data.Union
 import Info hiding (Empty, Go)
 import Language
 import Language.Markdown
+import qualified Language.JSON.Syntax as JSON
 import qualified Language.Markdown.Syntax as Markdown
 import qualified Language.Python.Syntax as Python
 import qualified Language.Ruby.Syntax as Ruby
@@ -34,6 +36,7 @@ import Text.Parser.TreeSitter.Go
 import Text.Parser.TreeSitter.Python
 import Text.Parser.TreeSitter.Ruby
 import Text.Parser.TreeSitter.TypeScript
+import Text.Parser.TreeSitter.JSON
 import TreeSitter
 
 -- | A parser from 'Source' onto some term type.
@@ -59,6 +62,7 @@ parserForLanguage Nothing = LineByLineParser
 parserForLanguage (Just language) = case language of
   C -> TreeSitterParser C tree_sitter_c
   Go -> TreeSitterParser Go tree_sitter_go
+  JSON -> TreeSitterParser JSON tree_sitter_json
   JavaScript -> TreeSitterParser TypeScript tree_sitter_typescript
   Ruby -> TreeSitterParser Ruby tree_sitter_ruby
   TypeScript -> TreeSitterParser TypeScript tree_sitter_typescript
@@ -70,6 +74,9 @@ rubyParser = AssignmentParser (ASTParser tree_sitter_ruby) headF Ruby.assignment
 pythonParser :: Parser Python.Term
 pythonParser = AssignmentParser (ASTParser tree_sitter_python) headF Python.assignment
 
+jsonParser :: Parser JSON.Term
+jsonParser = AssignmentParser (ASTParser tree_sitter_json) headF JSON.assignment
+
 markdownParser :: Parser Markdown.Term
 markdownParser = AssignmentParser MarkdownParser (\ (node@Node{..} :< _) -> node { nodeSymbol = toGrammar nodeSymbol }) Markdown.assignment
 

src/Semantic.hs

@@ -47,12 +47,15 @@ parseBlob renderer blob@Blob{..} = case (renderer, blobLanguage) of
   (ToCTermRenderer, _) -> parse syntaxParser blob >>= decorate (syntaxDeclarationAlgebra blob) >>= render (renderToCTerm blob)
   (JSONTermRenderer, Just Language.Markdown) -> parse markdownParser blob >>= decorate constructorLabel >>= render (renderJSONTerm blob)
   (JSONTermRenderer, Just Language.Python) -> parse pythonParser blob >>= decorate constructorLabel >>= render (renderJSONTerm blob)
+  (JSONTermRenderer, Just Language.JSON) -> parse jsonParser blob >>= decorate constructorLabel >>= render (renderJSONTerm blob)
   (JSONTermRenderer, _) -> parse syntaxParser blob >>= decorate identifierAlgebra >>= render (renderJSONTerm blob)
   (SExpressionTermRenderer, Just Language.Markdown) -> parse markdownParser blob >>= decorate constructorLabel >>= render renderSExpressionTerm . fmap keepConstructorLabel
   (SExpressionTermRenderer, Just Language.Python) -> parse pythonParser blob >>= decorate constructorLabel >>= render renderSExpressionTerm . fmap keepConstructorLabel
+  (SExpressionTermRenderer, Just Language.JSON) -> parse jsonParser blob >>= decorate constructorLabel >>= render renderSExpressionTerm . fmap keepConstructorLabel
   (SExpressionTermRenderer, _) -> parse syntaxParser blob >>= render renderSExpressionTerm . fmap keepCategory
   (IdentityTermRenderer, Just Language.Markdown) -> pure Nothing
   (IdentityTermRenderer, Just Language.Python) -> pure Nothing
+  (IdentityTermRenderer, Just Language.JSON) -> pure Nothing
   (IdentityTermRenderer, _) -> Just <$> parse syntaxParser blob
   where syntaxParser = parserForLanguage blobLanguage
 
@@ -69,12 +72,15 @@ diffBlobPair renderer blobs = case (renderer, effectiveLanguage) of
   (ToCDiffRenderer, _) -> run (\ blob -> parse syntaxParser blob >>= decorate (syntaxDeclarationAlgebra blob)) diffTerms (renderToCDiff blobs)
   (JSONDiffRenderer, Just Language.Markdown) -> run (parse markdownParser) diffLinearly (renderJSONDiff blobs)
   (JSONDiffRenderer, Just Language.Python) -> run (parse pythonParser) diffLinearly (renderJSONDiff blobs)
+  (JSONDiffRenderer, Just Language.JSON) -> run (parse jsonParser) diffLinearly (renderJSONDiff blobs)
   (JSONDiffRenderer, _) -> run (decorate identifierAlgebra <=< parse syntaxParser) diffTerms (renderJSONDiff blobs)
   (PatchDiffRenderer, Just Language.Markdown) -> run (parse markdownParser) diffLinearly (renderPatch blobs)
   (PatchDiffRenderer, Just Language.Python) -> run (parse pythonParser) diffLinearly (renderPatch blobs)
+  (PatchDiffRenderer, Just Language.JSON) -> run (parse jsonParser) diffLinearly (renderPatch blobs)
   (PatchDiffRenderer, _) -> run (parse syntaxParser) diffTerms (renderPatch blobs)
   (SExpressionDiffRenderer, Just Language.Markdown) -> run (decorate constructorLabel <=< parse markdownParser) diffLinearly (renderSExpressionDiff . mapAnnotations keepConstructorLabel)
   (SExpressionDiffRenderer, Just Language.Python) -> run (decorate constructorLabel <=< parse pythonParser) diffLinearly (renderSExpressionDiff . mapAnnotations keepConstructorLabel)
+  (SExpressionDiffRenderer, Just Language.JSON) -> run (decorate constructorLabel <=< parse jsonParser) diffLinearly (renderSExpressionDiff . mapAnnotations keepConstructorLabel)
   (SExpressionDiffRenderer, _) -> run (parse syntaxParser) diffTerms (renderSExpressionDiff . mapAnnotations keepCategory)
   (IdentityDiffRenderer, _) -> run (\ blob -> parse syntaxParser blob >>= decorate (syntaxDeclarationAlgebra blob)) diffTerms Just
   where effectiveLanguage = runBothWith (<|>) (blobLanguage <$> blobs)