Merge pull request #100 from DetachHead/transformNonNullExpressions

woutervh- · web-flow · commit 68c0bf856677 · 2021-11-01T10:39:41.000+01:00
add transformNonNullExpressions
diff --git a/README.md b/README.md
@@ -137,6 +137,7 @@ There are some options to configure the transformer.
 | `ignoreFunctions` *(deprecated, use `functionBehavior` instead)* | Boolean (default: `false`). If `true`, when the transformer encounters a function, it will ignore it and simply return `true`. If `false`, an error is generated at compile time. |
 | `functionBehavior` | One of `error`, `ignore`, or `basic` (default: `error`). Determines the behavior of transformer when encountering a function. `error` will cause a compile-time error, `ignore` will cause the validation function to always return `true`, and `basic` will do a simple function-type-check. Overrides `ignoreFunctions`. |
 | `disallowSuperfluousObjectProperties` | Boolean (default: `false`). If `true`, objects are checked for having superfluous properties and will cause the validation to fail if they do. If `false`, no check for superfluous properties is made. |
+| `transformNonNullExpressions` | Boolean (default: `false`). If `true`, non-null expressions (eg. `foo!.bar`) are checked to not be `null` or `undefined` |
 
 If you are using `ttypescript`, you can include the options in your `tsconfig.json`:
 
@@ -150,7 +151,8 @@ If you are using `ttypescript`, you can include the options in your `tsconfig.js
                 "ignoreClasses": true,
                 "ignoreMethods": true,
                 "functionBehavior": "ignore",
-                "disallowSuperfluousObjectProperties": true
+                "disallowSuperfluousObjectProperties": true,
+                "transformNonNullExpressions": true
             }
         ]
     }
diff --git a/src/transform-inline/transform-node.ts b/src/transform-inline/transform-node.ts
@@ -132,6 +132,55 @@ export function transformNode(node: ts.Node, visitorContext: PartialVisitorConte
                 ]
             );
         }
+    } else if (visitorContext.options.transformNonNullExpressions && ts.isNonNullExpression(node)) {
+        const expression = node.expression
+        return ts.factory.updateNonNullExpression(node, ts.factory.createParenthesizedExpression(ts.factory.createConditionalExpression(
+            ts.factory.createParenthesizedExpression(ts.factory.createBinaryExpression(
+                ts.factory.createBinaryExpression(
+                    ts.factory.createTypeOfExpression(expression),
+                    ts.factory.createToken(ts.SyntaxKind.EqualsEqualsEqualsToken),
+                    ts.factory.createStringLiteral('undefined')
+                ),
+                ts.factory.createToken(ts.SyntaxKind.BarBarToken),
+                ts.factory.createBinaryExpression(
+                    expression,
+                    ts.factory.createToken(ts.SyntaxKind.EqualsEqualsEqualsToken),
+                    ts.factory.createNull()
+                )
+            )),
+            ts.factory.createToken(ts.SyntaxKind.QuestionToken),
+            ts.factory.createCallExpression(
+                ts.factory.createParenthesizedExpression(ts.factory.createArrowFunction(
+                    undefined,
+                    undefined,
+                    [],
+                    undefined,
+                    ts.factory.createToken(ts.SyntaxKind.EqualsGreaterThanToken),
+                    ts.factory.createBlock(
+                        [ts.factory.createThrowStatement(ts.factory.createNewExpression(
+                            ts.factory.createIdentifier('Error'),
+                            undefined,
+                            [ts.factory.createTemplateExpression(
+                                ts.factory.createTemplateHead(`${expression.getText()} was non-null asserted but is `),
+                                [ts.factory.createTemplateSpan(
+                                    expression,
+                                    ts.factory.createTemplateTail(
+                                        ''
+                                    )
+                                )]
+                            )]
+                        ))
+                        ],
+                        false
+                    )
+                )),
+                undefined,
+                []
+            ),
+            ts.factory.createToken(ts.SyntaxKind.ColonToken),
+            expression
+        )))
     }
     return node;
 }
+
diff --git a/src/transform-inline/transformer.ts b/src/transform-inline/transformer.ts
@@ -32,7 +32,8 @@ export default function transformer(program: ts.Program, options?: { [Key: strin
             ignoreClasses: !!(options && options.ignoreClasses),
             ignoreMethods: !!(options && options.ignoreMethods),
             functionBehavior: getFunctionBehavior(options),
-            disallowSuperfluousObjectProperties: !!(options && options.disallowSuperfluousObjectProperties)
+            disallowSuperfluousObjectProperties: !!(options && options.disallowSuperfluousObjectProperties),
+            transformNonNullExpressions: !!(options && options.transformNonNullExpressions)
         },
         typeMapperStack: [],
         previousTypeReference: null
diff --git a/src/transform-inline/visitor-context.d.ts b/src/transform-inline/visitor-context.d.ts
@@ -6,6 +6,7 @@ interface Options {
     ignoreMethods: boolean;
     functionBehavior: 'error' | 'ignore' | 'basic';
     disallowSuperfluousObjectProperties: boolean;
+    transformNonNullExpressions: boolean;
 }
 
 export interface VisitorContext extends PartialVisitorContext {
diff --git a/test/issue-16.ts b/test/issue-16.ts
@@ -36,7 +36,8 @@ describe('visitor', () => {
                     ignoreMethods: false,
                     functionBehavior: 'error',
                     shortCircuit: false,
-                    disallowSuperfluousObjectProperties: false
+                    disallowSuperfluousObjectProperties: false,
+                    transformNonNullExpressions: false
                 },
                 typeMapperStack: [],
                 previousTypeReference: null
@@ -61,7 +62,8 @@ describe('visitor', () => {
                     ignoreMethods: false,
                     functionBehavior: 'error',
                     shortCircuit: false,
-                    disallowSuperfluousObjectProperties: false
+                    disallowSuperfluousObjectProperties: false,
+                    transformNonNullExpressions: false
                 },
                 typeMapperStack: [],
                 previousTypeReference: null
@@ -90,7 +92,8 @@ describe('visitor', () => {
                 ignoreMethods: true,
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
@@ -118,7 +121,8 @@ describe('visitor', () => {
                 ignoreMethods: false,
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
@@ -146,7 +150,8 @@ describe('visitor', () => {
                 ignoreMethods: true,
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
diff --git a/test/issue-27.ts b/test/issue-27.ts
@@ -34,7 +34,8 @@ describe('visitor', () => {
                 ignoreMethods: true,
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
diff --git a/test/issue-3.ts b/test/issue-3.ts
@@ -35,7 +35,8 @@ describe('visitor', () => {
                 ignoreMethods: false,
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
diff --git a/test/issue-31.ts b/test/issue-31.ts
@@ -45,7 +45,8 @@ describe('visitor', () => {
             ignoreMethods: true, // Make sure it does not fail on the methods.
             functionBehavior: 'error',
             shortCircuit: false,
-            disallowSuperfluousObjectProperties: false
+            disallowSuperfluousObjectProperties: false,
+            transformNonNullExpressions: false
         };
         const visitorContext = createVisitorContext(program, options);
         const visitorContextWithDate = createVisitorContext(programWithDate, options);
@@ -77,7 +78,8 @@ describe('visitor', () => {
             ignoreMethods: false, // It should never get to the methods of the class.
             functionBehavior: 'error',
             shortCircuit: false,
-            disallowSuperfluousObjectProperties: false
+            disallowSuperfluousObjectProperties: false,
+            transformNonNullExpressions: false
         };
         const visitorContext = createVisitorContext(program, options);
         const visitorContextWithDate = createVisitorContext(programWithDate, options);
diff --git a/test/issue-50.ts b/test/issue-50.ts
@@ -35,7 +35,8 @@ describe('visitor', () => {
                 ignoreMethods: true, // Make sure that the function is not seen as a method.
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
@@ -63,7 +64,8 @@ describe('visitor', () => {
                 ignoreMethods: false,
                 functionBehavior: 'ignore',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
diff --git a/test/issue-52.ts b/test/issue-52.ts
@@ -35,7 +35,8 @@ describe('visitor', () => {
                 ignoreMethods: true, // Make sure that the function is not seen as a method.
                 functionBehavior: 'error',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
@@ -63,7 +64,8 @@ describe('visitor', () => {
                 ignoreMethods: false,
                 functionBehavior: 'ignore',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
@@ -91,7 +93,8 @@ describe('visitor', () => {
                 ignoreMethods: false,
                 functionBehavior: 'basic',
                 shortCircuit: false,
-                disallowSuperfluousObjectProperties: false
+                disallowSuperfluousObjectProperties: false,
+                transformNonNullExpressions: false
             },
             typeMapperStack: [],
             previousTypeReference: null
diff --git a/test/issue-98.ts b/test/issue-98.ts
@@ -0,0 +1,16 @@
+import * as assert from 'assert';
+
+describe('transformNonNullAssertions', () => {
+    it('should be null', () => {
+        const foo: { bar: number | null } = {bar: null}
+        assert.throws(() => foo.bar!, {message: 'foo.bar was non-null asserted but is null'})
+    })
+    it('should be undefined', () => {
+        const foo: { bar?: number } = {}
+        assert.throws(() => foo.bar!, {message: 'foo.bar was non-null asserted but is undefined'})
+    })
+    it('should not throw', () => {
+        const foo: { bar?: number } = {bar: 1}
+        assert.equal(foo.bar!, 1)
+    })
+})
diff --git a/tsconfig-test.json b/tsconfig-test.json
@@ -13,11 +13,12 @@
         "declaration": false,
         "plugins": [
             {
-                "transform": "./src/transform-inline/transformer.ts"
+                "transform": "./src/transform-inline/transformer.ts",
+                "transformNonNullExpressions": true
             }
         ]
     },
     "include": [
         "test"
     ]
-}
+}

Original file line number	Diff line number	Diff line change
`@@ -137,6 +137,7 @@ There are some options to configure the transformer.`
`137`	`137`	\| `ignoreFunctions` (deprecated, use `functionBehavior` instead) \| Boolean (default: `false`). If `true`, when the transformer encounters a function, it will ignore it and simply return `true`. If `false`, an error is generated at compile time. \|
`138`	`138`	\| `functionBehavior` \| One of `error`, `ignore`, or `basic` (default: `error`). Determines the behavior of transformer when encountering a function. `error` will cause a compile-time error, `ignore` will cause the validation function to always return `true`, and `basic` will do a simple function-type-check. Overrides `ignoreFunctions`. \|
`139`	`139`	\| `disallowSuperfluousObjectProperties` \| Boolean (default: `false`). If `true`, objects are checked for having superfluous properties and will cause the validation to fail if they do. If `false`, no check for superfluous properties is made. \|
	`140`	+\| `transformNonNullExpressions` \| Boolean (default: `false`). If `true`, non-null expressions (eg. `foo!.bar`) are checked to not be `null` or `undefined` \|
`140`	`141`
`141`	`142`	If you are using `ttypescript`, you can include the options in your `tsconfig.json`:
`142`	`143`
@@ -150,7 +151,8 @@ If you are using `ttypescript`, you can include the options in your `tsconfig.js
`150`	`151`	`"ignoreClasses": true,`
`151`	`152`	`"ignoreMethods": true,`
`152`	`153`	`"functionBehavior": "ignore",`
`153`		`- "disallowSuperfluousObjectProperties": true`
	`154`	`+ "disallowSuperfluousObjectProperties": true,`
	`155`	`+ "transformNonNullExpressions": true`
`154`	`156`	`}`
`155`	`157`	`]`
`156`	`158`	`}`
Original file line number	Diff line number	Diff line change
`@@ -6,6 +6,7 @@ interface Options {`
`6`	`6`	`ignoreMethods: boolean;`
`7`	`7`	`functionBehavior: 'error' \| 'ignore' \| 'basic';`
`8`	`8`	`disallowSuperfluousObjectProperties: boolean;`
	`9`	`+ transformNonNullExpressions: boolean;`
`9`	`10`	`}`
`10`	`11`
`11`	`12`	`export interface VisitorContext extends PartialVisitorContext {`