Throw an error if a helper is unknown

hazzard993 · hazzard993 · commit 6646695a558d · 2020-08-17T10:21:44.000+10:00
diff --git a/src/transformation/utils/diagnostics.ts b/src/transformation/utils/diagnostics.ts
@@ -127,8 +127,6 @@ export const unsupportedVarDeclaration = createDiagnosticFactory(
     "`var` declarations are not supported. Use `let` or `const` instead."
 );
 
-export const unknownHelperKind = createDiagnosticFactory((kind: string) => `Unknown helper kind "${kind}".`);
-
 export const invalidMultiFunctionUse = createDiagnosticFactory(
     "The $multi function must be called in return statements."
 );
diff --git a/src/transformation/utils/helpers.ts b/src/transformation/utils/helpers.ts
@@ -1,10 +1,9 @@
 import * as ts from "typescript";
 import * as path from "path";
-import { TransformationContext } from "../context";
-import { unknownHelperKind } from "./diagnostics";
 
 export enum HelperKind {
-    Multi = "multi",
+    MultiFunction = "MultiFunction",
+    MultiReturnFunction = "MultiReturnFunction",
 }
 
 function isSourceFileFromHelpers(sourceFile: ts.SourceFile): boolean {
@@ -13,14 +12,15 @@ function isSourceFileFromHelpers(sourceFile: ts.SourceFile): boolean {
     return helperDirectory === sourceFileDirectory;
 }
 
-export function getHelperFileKind(context: TransformationContext, sourceFile: ts.SourceFile): HelperKind | undefined {
+export function getHelperFileKind(declaration: ts.Declaration): HelperKind | undefined {
+    const sourceFile = declaration.getSourceFile();
     if (isSourceFileFromHelpers(sourceFile)) {
         const baseFileName = path.basename(sourceFile.fileName).replace(/(\.d)?\.ts$/g, "");
         switch (baseFileName) {
             case "multi":
-                return HelperKind.Multi;
+                return HelperKind.MultiReturnFunction;
             default:
-                context.diagnostics.push(unknownHelperKind(sourceFile, baseFileName));
+                throw new Error("Unknown helper");
         }
     }
 }
diff --git a/src/transformation/visitors/helpers/multi.ts b/src/transformation/visitors/helpers/multi.ts
@@ -18,12 +18,12 @@ import {
     invalidMultiFunctionUse,
 } from "../../../transformation/utils/diagnostics";
 
-const isMultiHelperDeclaration = (context: TransformationContext) => (declaration: ts.Declaration): boolean =>
-    helpers.getHelperFileKind(context, declaration.getSourceFile()) === helpers.HelperKind.Multi;
+const isMultiHelperDeclaration = (declaration: ts.Declaration): boolean =>
+    helpers.getHelperFileKind(declaration) === helpers.HelperKind.MultiFunction;
 
 function isMultiHelperCallSignature(context: TransformationContext, expression: ts.CallExpression): boolean {
     const type = context.checker.getTypeAtLocation(expression.expression);
-    return type.symbol?.declarations?.some(isMultiHelperDeclaration(context)) ?? false;
+    return type.symbol?.declarations?.some(isMultiHelperDeclaration) ?? false;
 }
 
 export function isMultiReturnCall(context: TransformationContext, node: ts.Node): node is ts.CallExpression {
@@ -32,12 +32,12 @@ export function isMultiReturnCall(context: TransformationContext, node: ts.Node)
     }
 
     const signature = context.checker.getResolvedSignature(node);
-    return signature?.getReturnType().aliasSymbol?.declarations?.some(isMultiHelperDeclaration(context)) ?? false;
+    return signature?.getReturnType().aliasSymbol?.declarations?.some(isMultiHelperDeclaration) ?? false;
 }
 
 export function isMultiHelperNode(context: TransformationContext, node: ts.Node): boolean {
     const type = context.checker.getTypeAtLocation(node);
-    return type.symbol?.declarations?.some(isMultiHelperDeclaration(context)) ?? false;
+    return type.symbol?.declarations?.some(isMultiHelperDeclaration) ?? false;
 }
 
 export function transformMultiHelperReturnStatement(
@@ -158,7 +158,7 @@ export function findMultiHelperAssignmentViolations(
             const valueSymbol = context.checker.getShorthandAssignmentValueSymbol(element);
             if (valueSymbol) {
                 const declaration = valueSymbol.valueDeclaration;
-                if (declaration && isMultiHelperDeclaration(context)(declaration)) {
+                if (declaration && isMultiHelperDeclaration(declaration)) {
                     context.diagnostics.push(invalidMultiFunctionUse(element));
                     return element;
                 }

Original file line number	Diff line number	Diff line change
`@@ -1,10 +1,9 @@`
`1`	`1`	`import * as ts from "typescript";`
`2`	`2`	`import * as path from "path";`
`3`		`-import { TransformationContext } from "../context";`
`4`		`-import { unknownHelperKind } from "./diagnostics";`
`5`	`3`
`6`	`4`	`export enum HelperKind {`
`7`		`- Multi = "multi",`
	`5`	`+ MultiFunction = "MultiFunction",`
	`6`	`+ MultiReturnFunction = "MultiReturnFunction",`
`8`	`7`	`}`
`9`	`8`
`10`	`9`	`function isSourceFileFromHelpers(sourceFile: ts.SourceFile): boolean {`
`@@ -13,14 +12,15 @@ function isSourceFileFromHelpers(sourceFile: ts.SourceFile): boolean {`
`13`	`12`	`return helperDirectory === sourceFileDirectory;`
`14`	`13`	`}`
`15`	`14`
`16`		`-export function getHelperFileKind(context: TransformationContext, sourceFile: ts.SourceFile): HelperKind \| undefined {`
	`15`	`+export function getHelperFileKind(declaration: ts.Declaration): HelperKind \| undefined {`
	`16`	`+ const sourceFile = declaration.getSourceFile();`
`17`	`17`	`if (isSourceFileFromHelpers(sourceFile)) {`
`18`	`18`	`const baseFileName = path.basename(sourceFile.fileName).replace(/(\.d)?\.ts$/g, "");`
`19`	`19`	`switch (baseFileName) {`
`20`	`20`	`case "multi":`
`21`		`- return HelperKind.Multi;`
	`21`	`+ return HelperKind.MultiReturnFunction;`
`22`	`22`	`default:`
`23`		`- context.diagnostics.push(unknownHelperKind(sourceFile, baseFileName));`
	`23`	`+ throw new Error("Unknown helper");`
`24`	`24`	`}`
`25`	`25`	`}`
`26`	`26`	`}`