perf(ternary-operator-parser): improve performance

kantord · Dec 23, 2018 · cc324d1 · cc324d1
1 parent df5b91d
commit cc324d1
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Showing 5 changed files with 40 additions and 52 deletions.
diff --git a/src/__tests__/__snapshots__/interpreter.test.js.snap b/src/__tests__/__snapshots__/interpreter.test.js.snap
@@ -5965,17 +5965,7 @@ exports[`interpreter correct target tree 3 + 4 if 2 <= 3 else -12 1`] = `
 Object {
   "status": true,
   "value": Object {
-    "end": Object {
-      "column": 25,
-      "line": 1,
-      "offset": 24,
-    },
     "name": "ternary",
-    "start": Object {
-      "column": 1,
-      "line": 1,
-      "offset": 0,
-    },
     "value": Object {
       "left": Object {
         "name": "binaryOperation",
@@ -6047,17 +6037,7 @@ Object {
     "name": "pipe",
     "value": Object {
       "left": Object {
-        "end": Object {
-          "column": 25,
-          "line": 1,
-          "offset": 24,
-        },
         "name": "ternary",
-        "start": Object {
-          "column": 1,
-          "line": 1,
-          "offset": 0,
-        },
         "value": Object {
           "left": Object {
             "name": "tuple",
@@ -6417,17 +6397,7 @@ exports[`interpreter correct target tree error "Hello" if false else "asdfgb" 1`
 Object {
   "status": true,
   "value": Object {
-    "end": Object {
-      "column": 37,
-      "line": 1,
-      "offset": 36,
-    },
     "name": "ternary",
-    "start": Object {
-      "column": 1,
-      "line": 1,
-      "offset": 0,
-    },
     "value": Object {
       "left": Object {
         "name": "functionCall",

diff --git a/src/__tests__/descriptions.test.js b/src/__tests__/descriptions.test.js
@@ -20,7 +20,8 @@ const exclude = [
   'program.js',
   'operands',
   'collections',
-  'pipe.js'
+  'pipe.js',
+  'ternary.js'
 ]
 const files = fs
   .readdirSync(path.join(__dirname, '..', 'parsers'))

diff --git a/src/parsers/__tests__/ternary.test.js b/src/parsers/__tests__/ternary.test.js
@@ -18,4 +18,11 @@ describe('ternary parser', () => {
       }
     })
   })
+
+  it('handles tuple correctly', () => {
+    expect(parser.parse('0').value).toMatchObject({
+      name: 'primitive',
+      value: '0'
+    })
+  })
 })
diff --git a/src/parsers/pipe.js b/src/parsers/pipe.js
@@ -5,11 +5,9 @@ import P from 'parsimmon'
 import type { NodeType } from '../types'
 
 const PipeParser = P.lazy((): mixed => {
-  const TupleParser = require('./collections/tuple').default
   const TernaryParser = require('./ternary').default
-  return P.alt(TernaryParser, TupleParser)
-    .sepBy1(P.regexp(/\s*\|\s*/))
-    .map((value: Array<NodeType>): NodeType =>
+  return TernaryParser.sepBy1(P.regexp(/\s*\|\s*/)).map(
+    (value: Array<NodeType>): NodeType =>
       value.slice(1).reduce(
         (a: NodeType, b: NodeType): NodeType => ({
           name: 'pipe',
@@ -20,7 +18,7 @@ const PipeParser = P.lazy((): mixed => {
         }),
         value[0]
       )
-    )
+  )
 })
 
 export default PipeParser
diff --git a/src/parsers/ternary.js b/src/parsers/ternary.js
@@ -3,26 +3,38 @@
 import P from 'parsimmon'
 import crap from './crap'
 
-import type { TupleNodeType, TernaryNodeValueType, ParserType } from '../types'
+import type {
+  TupleNodeType,
+  ParserType,
+  NodeType
+} from '../types'
 
 export default P.lazy((): ParserType => {
   const TupleParser = require('./collections/tuple').default
   return P.seq(
     TupleParser,
-    P.string('if')
-      .trim(crap)
-      .then(TupleParser),
-    P.string('else')
-      .trim(crap)
-      .then(TupleParser)
+    P.seq(
+      P.string('if')
+        .trim(crap)
+        .then(TupleParser),
+      P.string('else')
+        .trim(crap)
+        .then(TupleParser)
+    ).atMost(1)
+  ).map(
+    ([tuple, rest]: [
+      TupleNodeType,
+      Array<[TupleNodeType, TupleNodeType]>
+    ]): NodeType =>
+      rest.length === 0
+        ? tuple
+        : {
+          name: 'ternary',
+          value: {
+            left: tuple,
+            middle: rest[0][0],
+            right: rest[0][1]
+          }
+        }
   )
-    .map(
-      ([left, middle, right]: [
-        TupleNodeType,
-        TupleNodeType,
-        TupleParser
-      ]): TernaryNodeValueType => ({ left, middle, right })
-    )
-    .node('ternary')
-    .desc('ternary')
 })