Fix error message for babel#4 case

This impact private fields as well as smart pipeline, providing a clearer
error message for both.

packages/babel-parser/src/tokenizer/index.js

@@ -412,6 +412,10 @@ export default class Tokenizer extends LocationParser {
 
     const nextPos = this.state.pos + 1;
     const next = this.input.charCodeAt(nextPos);
+    if (next >= charCodes.digit0 && next <= charCodes.digit9) {
+      this.raise(this.state.pos, "Unexpected digit after hash token");
+    }
+
     if (
       (this.hasPlugin("classPrivateProperties") ||
         this.hasPlugin("classPrivateMethods")) &&
@@ -423,16 +427,7 @@ export default class Tokenizer extends LocationParser {
     } else if (
       this.getPluginOption("pipelineOperator", "proposal") === "smart"
     ) {
-      if (next >= charCodes.digit0 && next <= charCodes.digit9) {
-        this.raise(
-          this.state.pos,
-          `Unexpected digit after topic reference: '#${String.fromCodePoint(
-            next,
-          )}'`,
-        );
-      } else {
-        this.finishOp(tt.hash, 1);
-      }
+      this.finishOp(tt.hash, 1);
     } else {
       this.raise(
         this.state.pos,

packages/babel-parser/test/fixtures/experimental/class-private-properties/failure-numeric-literal/options.json

@@ -1,4 +1,4 @@
 {
-  "throws": "Unexpected token (2:3)",
+  "throws": "Unexpected digit after hash token (2:2)",
   "plugins": [ "classPrivateProperties" ]
 }

packages/babel-parser/test/fixtures/experimental/class-private-properties/failure-numeric-start-identifier/options.json

@@ -1,4 +1,4 @@
 {
-  "throws": "Identifier directly after number (2:4)",
+  "throws": "Unexpected digit after hash token (2:2)",
   "plugins": ["classPrivateProperties"]
 }

packages/babel-parser/test/fixtures/experimental/pipeline-operator/proposal-smart-error,-invalid-hash-token,-followed-by-digit/options.json

@@ -1,4 +1,4 @@
 {
   "plugins": [["pipelineOperator", { "proposal": "smart" }]],
-  "throws": "Unexpected digit after topic reference: '#4' (1:5)"
+  "throws": "Unexpected digit after hash token (1:5)"
 }