perf(projection-parser): improve performance by reorganizing parser

kantord · Dec 24, 2018 · 5d74903 · 5d74903
1 parent 27dedef
commit 5d74903
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Showing 2 changed files with 25 additions and 20 deletions.
diff --git a/src/__tests__/__snapshots__/interpreter.test.js.snap b/src/__tests__/__snapshots__/interpreter.test.js.snap
@@ -1905,9 +1905,9 @@ Object {
     "value": Array [
       Object {
         "end": Object {
-          "column": 18,
+          "column": 20,
           "line": 1,
-          "offset": 17,
+          "offset": 19,
         },
         "name": "simpleList",
         "start": Object {
@@ -1983,9 +1983,9 @@ Object {
                             "value": Array [
                               Object {
                                 "end": Object {
-                                  "column": 14,
+                                  "column": 15,
                                   "line": 1,
-                                  "offset": 13,
+                                  "offset": 14,
                                 },
                                 "name": "simpleList",
                                 "start": Object {
@@ -3842,9 +3842,9 @@ Object {
     "value": Array [
       Object {
         "end": Object {
-          "column": 8,
-          "line": 5,
-          "offset": 80,
+          "column": 5,
+          "line": 6,
+          "offset": 85,
         },
         "name": "simpleList",
         "start": Object {
@@ -3941,9 +3941,9 @@ Object {
                 "value": Array [
                   Object {
                     "end": Object {
-                      "column": 33,
-                      "line": 4,
-                      "offset": 72,
+                      "column": 7,
+                      "line": 5,
+                      "offset": 79,
                     },
                     "name": "simpleList",
                     "start": Object {

diff --git a/src/parsers/projection.js b/src/parsers/projection.js
@@ -7,7 +7,8 @@ import type {
   ListNodeType,
   ProjectionNodeType,
   ValuePropNodeType,
-  ProjectableNodeType
+  ProjectableNodeType,
+  NodeType
 } from '../types'
 
 type WrappedProjectionNodeType =
@@ -82,15 +83,19 @@ const ProjectionParser = P.lazy((): mixed => {
     packProperty
   )
 
-  return P.alt(
-    P.seq(
-      ProjectableParser.skip(crap),
-      P.alt(ProjectionParser, PropertyParser)
-        .skip(crap)
-        .atLeast(1)
-    ).map(unpack),
-    ProjectableParser
-  ).desc('projection')
+  return P.seq(
+    ProjectableParser.skip(crap),
+    P.alt(ProjectionParser, PropertyParser)
+      .skip(crap)
+      .many()
+  )
+    .map(
+      ([left, right]: [
+        ProjectableNodeType,
+        Array<WrappedProjectionNodeWithOptionalType>
+      ]): NodeType => (right.length === 0 ? left : unpack([left, right]))
+    )
+    .desc('projection')
 })
 
 export default ProjectionParser