parser: Support percentage topic with v8intrinsics

packages/babel-parser/src/parser/expression.js

@@ -1268,14 +1268,26 @@ export default class ExpressionParser extends LValParser {
     }
   }
 
-  // https://github.com/js-choi/proposal-hack-pipes
+  // This helper method attempts to parse a topic reference
+  // into a new node.
+  // See <https://github.com/js-choi/proposal-hack-pipes>.
+  //
+  // If the `pipelineOperator` plugin is active,
+  // and if the given `tokenType` matches the plugin’s configuration,
+  // then this method will return a new node.
+  //
+  // If the `pipelineOperator` plugin is active,
+  // but if the given `tokenType` does not match the plugin’s configuration,
+  // then this method will throw a `PipeTopicUnconfiguredToken` error.
+  //
+  // When an appropriate `pipelineOperator` proposal is not active,
+  // this method returns `undefined`.
   maybeParseTopicReference(): ?N.Expression {
-    const pipeProposal = this.getPluginOption("pipelineOperator", "proposal");
-
     // `pipeProposal` is falsy when an input program
     // contains a topic reference on its own,
     // outside of a pipe expression,
     // and without having turned on the pipelineOperator plugin.
+    const pipeProposal = this.getPluginOption("pipelineOperator", "proposal");
     if (pipeProposal) {
       // A pipe-operator proposal is active.
 
@@ -1287,48 +1299,62 @@ export default class ExpressionParser extends LValParser {
 
         const node = this.startNode();
 
-        // Determine the node type for the topic reference
-        // that is appropriate for the active pipe-operator proposal.
-        let nodeType;
-        if (pipeProposal === "smart") {
-          nodeType = "PipelinePrimaryTopicReference";
-        } else {
-          // The proposal must otherwise be "hack",
-          // as enforced by testTopicReferenceConfiguration.
-          nodeType = "TopicReference";
-        }
-
         // Consume the token.
         this.next();
 
-        // Register the topic reference so that its pipe body knows
-        // that its topic was used at least once.
-        this.registerTopicReference();
-
-        if (!this.topicReferenceIsAllowedInCurrentContext()) {
-          // The topic reference is not allowed in the current context:
-          // it is outside of a pipe body.
-          // Raise recoverable errors.
-          if (pipeProposal === "smart") {
-            this.raise(this.state.start, Errors.PrimaryTopicNotAllowed);
-          } else {
-            // In this case, `pipeProposal === "hack"` is true.
-            this.raise(this.state.start, Errors.PipeTopicUnbound);
-          }
-        }
+        const start = this.state.start;
 
-        return this.finishNode(node, nodeType);
+        return this.finishTopicReferenceNode(node, start, pipeProposal);
       } else {
         // The token does not match the plugin’s configuration.
+        const start = this.state.start;
         throw this.raise(
-          this.state.start,
+          start,
           Errors.PipeTopicUnconfiguredToken,
           tokenType.label,
         );
       }
     }
   }
 
+  // This helper method attempts to finish the given `node`
+  // into a topic-reference node for the given `pipeProposal`.
+  // The method assumes that any topic token was consumed before it was called.
+  finishTopicReferenceNode(
+    node: N.Node,
+    start: int,
+    pipeProposal: string,
+  ): ?N.Expression {
+    // Determine the node type for the topic reference
+    // that is appropriate for the active pipe-operator proposal.
+    let nodeType;
+    if (pipeProposal === "smart") {
+      nodeType = "PipelinePrimaryTopicReference";
+    } else {
+      // The proposal must otherwise be "hack",
+      // as enforced by testTopicReferenceConfiguration.
+      nodeType = "TopicReference";
+    }
+
+    if (!this.topicReferenceIsAllowedInCurrentContext()) {
+      // The topic reference is not allowed in the current context:
+      // it is outside of a pipe body.
+      // Raise recoverable errors.
+      if (pipeProposal === "smart") {
+        this.raise(start, Errors.PrimaryTopicNotAllowed);
+      } else {
+        // In this case, `pipeProposal === "hack"` is true.
+        this.raise(start, Errors.PipeTopicUnbound);
+      }
+    }
+
+    // Register the topic reference so that its pipe body knows
+    // that its topic was used at least once.
+    this.registerTopicReference();
+
+    return this.finishNode(node, nodeType);
+  }
+
   // This helper method tests whether the given token type
   // matches the pipelineOperator parser plugin’s configuration.
   // If the active pipe proposal is Hack style,

packages/babel-parser/src/plugins/v8intrinsic.js

@@ -1,12 +1,13 @@
 import type Parser from "../parser";
 import { types as tt } from "../tokenizer/types";
 import * as N from "../types";
+import { Errors } from "../parser/error";
 
 export default (superClass: Class<Parser>): Class<Parser> =>
   class extends superClass {
     parseV8Intrinsic(): N.Expression {
       if (this.match(tt.modulo)) {
-        const v8IntrinsicStart = this.state.start;
+        const start = this.state.start;
         // let the `loc` of Identifier starts from `%`
         const node = this.startNode();
         this.eat(tt.modulo);
@@ -18,7 +19,39 @@ export default (superClass: Class<Parser>): Class<Parser> =>
             return identifier;
           }
         }
-        this.unexpected(v8IntrinsicStart);
+
+        // In this case, the `%` currently being parsed is not followed by an identifier,
+        // so it therefore cannot be a V8 intrinsic.
+        // If the `pipelineOperator` plugin is active,
+        // then the `%` currently being parsed may instead be a topic reference.
+        const pipeProposal = this.getPluginOption(
+          "pipelineOperator",
+          "proposal",
+        );
+
+        if (pipeProposal) {
+          // A pipe-operator proposal is active.
+          const moduloTopicTokenIsActive = this.testTopicReferenceConfiguration(
+            pipeProposal,
+            tt.modulo,
+          );
+
+          if (moduloTopicTokenIsActive) {
+            // The token matches the plugin’s configuration.
+            // The token is therefore a topic reference.
+            return this.finishTopicReferenceNode(node, start, pipeProposal);
+          } else {
+            // The token does not match the plugin’s configuration.
+            throw this.raise(
+              start,
+              Errors.PipeTopicUnconfiguredToken,
+              tt.modulo.label,
+            );
+          }
+        } else {
+          // A pipe-operator proposal is not active.
+          this.unexpected(start);
+        }
       }
     }
 

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-with-hash/input.js

@@ -0,0 +1 @@
+input |> %GetOptimizationStatus(#);

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-with-hash/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["pipelineOperator", { "proposal": "hack", "topicToken": "#" }],
+    "v8intrinsic"
+  ]
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-with-hash/output.json

@@ -0,0 +1,42 @@
+{
+  "type": "File",
+  "start":0,"end":35,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":35,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start":0,"end":35,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35}},
+        "expression": {
+          "type": "BinaryExpression",
+          "start":0,"end":34,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":34}},
+          "left": {
+            "type": "Identifier",
+            "start":0,"end":5,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":5},"identifierName":"input"},
+            "name": "input"
+          },
+          "operator": "|>",
+          "right": {
+            "type": "CallExpression",
+            "start":9,"end":34,"loc":{"start":{"line":1,"column":9},"end":{"line":1,"column":34}},
+            "callee": {
+              "type": "V8IntrinsicIdentifier",
+              "start":9,"end":31,"loc":{"start":{"line":1,"column":9},"end":{"line":1,"column":31},"identifierName":"GetOptimizationStatus"},
+              "name": "GetOptimizationStatus"
+            },
+            "arguments": [
+              {
+                "type": "TopicReference",
+                "start":32,"end":33,"loc":{"start":{"line":1,"column":32},"end":{"line":1,"column":33}}
+              }
+            ]
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-with-percent/input.js

@@ -0,0 +1 @@
+input |> %GetOptimizationStatus(%);

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-with-percent/options.json

@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    ["pipelineOperator", { "proposal": "hack", "topicToken": "#" }],
+    "v8intrinsic"
+  ],
+  "throws": "Invalid topic token %. In order to use % as a topic reference, the pipelineOperator plugin must be configured with { \"proposal\": \"hack\", \"topicToken\": \"%\" }. (1:32)"
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-without-topic/input.js

@@ -0,0 +1 @@
+input |> %GetOptimizationStatus(f);

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-without-topic/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["pipelineOperator", { "proposal": "hack", "topicToken": "%" }],
+    "v8intrinsic"
+  ]
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-hash-proposal-v8intrinsic-without-topic/output.json

@@ -0,0 +1,46 @@
+{
+  "type": "File",
+  "start":0,"end":35,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35}},
+  "errors": [
+    "SyntaxError: Hack-style pipe body does not contain a topic reference; Hack-style pipes must use topic at least once. (1:9)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":35,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start":0,"end":35,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35}},
+        "expression": {
+          "type": "BinaryExpression",
+          "start":0,"end":34,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":34}},
+          "left": {
+            "type": "Identifier",
+            "start":0,"end":5,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":5},"identifierName":"input"},
+            "name": "input"
+          },
+          "operator": "|>",
+          "right": {
+            "type": "CallExpression",
+            "start":9,"end":34,"loc":{"start":{"line":1,"column":9},"end":{"line":1,"column":34}},
+            "callee": {
+              "type": "V8IntrinsicIdentifier",
+              "start":9,"end":31,"loc":{"start":{"line":1,"column":9},"end":{"line":1,"column":31},"identifierName":"GetOptimizationStatus"},
+              "name": "GetOptimizationStatus"
+            },
+            "arguments": [
+              {
+                "type": "Identifier",
+                "start":32,"end":33,"loc":{"start":{"line":1,"column":32},"end":{"line":1,"column":33},"identifierName":"f"},
+                "name": "f"
+              }
+            ]
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-outside-pipe/input.js

@@ -0,0 +1 @@
+%GetOptimizationStatus(f);

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-outside-pipe/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["pipelineOperator", { "proposal": "hack", "topicToken": "%" }],
+    "v8intrinsic"
+  ]
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-outside-pipe/output.json

@@ -0,0 +1,33 @@
+{
+  "type": "File",
+  "start":0,"end":26,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":26}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":26,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":26}},
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start":0,"end":26,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":26}},
+        "expression": {
+          "type": "CallExpression",
+          "start":0,"end":25,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":25}},
+          "callee": {
+            "type": "V8IntrinsicIdentifier",
+            "start":0,"end":22,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":22},"identifierName":"GetOptimizationStatus"},
+            "name": "GetOptimizationStatus"
+          },
+          "arguments": [
+            {
+              "type": "Identifier",
+              "start":23,"end":24,"loc":{"start":{"line":1,"column":23},"end":{"line":1,"column":24},"identifierName":"f"},
+              "name": "f"
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-with-hash/input.js

@@ -0,0 +1 @@
+input |> %GetOptimizationStatus(#);

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-with-hash/options.json

@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    ["pipelineOperator", { "proposal": "hack", "topicToken": "%" }],
+    "v8intrinsic"
+  ],
+  "throws": "Invalid topic token #. In order to use # as a topic reference, the pipelineOperator plugin must be configured with { \"proposal\": \"hack\", \"topicToken\": \"#\" }. (1:32)"
+}

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-with-percent/input.js

@@ -0,0 +1 @@
+input |> %GetOptimizationStatus(%);

packages/babel-parser/test/fixtures/experimental/pipeline-operator/hack-percent-proposal-v8intrinsic-with-percent/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["pipelineOperator", { "proposal": "hack", "topicToken": "%" }],
+    "v8intrinsic"
+  ]
+}