Skip to content

switch typeof any could be checked for unreachable #39389

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 5 commits into from
Jul 21, 2020
Merged

switch typeof any could be checked for unreachable #39389

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
92cdf0f
switch typeof any could be checked for unreachable
ShuiRuTian Jul 2, 2020
e317a35
fix stupid error
ShuiRuTian Jul 3, 2020
9b5f6bd
support unknown
ShuiRuTian Jul 6, 2020
60ffcd7
remvoe use less code.
ShuiRuTian Jul 6, 2020
07b9bc5
fix spelling.
ShuiRuTian Jul 9, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions src/compiler/checker.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -131,6 +131,7 @@ namespace ts {
UndefinedFacts = TypeofNEString | TypeofNENumber | TypeofNEBigInt | TypeofNEBoolean | TypeofNESymbol | TypeofNEObject | TypeofNEFunction | TypeofNEHostObject | EQUndefined | EQUndefinedOrNull | NENull | Falsy,
NullFacts = TypeofEQObject | TypeofNEString | TypeofNENumber | TypeofNEBigInt | TypeofNEBoolean | TypeofNESymbol | TypeofNEFunction | TypeofNEHostObject | EQNull | EQUndefinedOrNull | NEUndefined | Falsy,
EmptyObjectStrictFacts = All & ~(EQUndefined | EQNull | EQUndefinedOrNull),
AllTypeofNE = TypeofNEString | TypeofNENumber | TypeofNEBigInt | TypeofNEBoolean | TypeofNESymbol | TypeofNEObject | TypeofNEFunction | NEUndefined,
EmptyObjectFacts = All,
}

Expand Down Expand Up @@ -28194,6 +28195,10 @@ namespace ts {
// notEqualFacts states that the type of the switched value is not equal to every type in the switch.
const notEqualFacts = getFactsFromTypeofSwitch(0, 0, witnesses, /*hasDefault*/ true);
const type = getBaseConstraintOfType(operandType) || operandType;
// Take any/unknown as a special condition. Or maybe we could change `type` to a union containing all primitive types.
if (type.flags & TypeFlags.AnyOrUnknown) {
return (TypeFacts.AllTypeofNE & notEqualFacts) === TypeFacts.AllTypeofNE;
}
return !!(filterType(type, t => (getTypeFacts(t) & notEqualFacts) === notEqualFacts).flags & TypeFlags.Never);
}
const type = getTypeOfExpression(node.expression);
Expand Down
19 changes: 19 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofAny.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,19 @@
tests/cases/compiler/unreachable.ts(12,5): error TS7027: Unreachable code detected.


==== tests/cases/compiler/unreachable.ts (1 errors) ====
const unreachable = (x: any): number => {
switch (typeof x) {
case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
~~
!!! error TS7027: Unreachable code detected.
}
29 changes: 29 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofAny.js
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,29 @@
//// [unreachable.ts]
const unreachable = (x: any): number => {
switch (typeof x) {
case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
}

//// [unreachable.js]
var unreachable = function (x) {
switch (typeof x) {
case 'string': return 0;
case 'number': return 0;
case 'bigint': return 0;
case 'boolean': return 0;
case 'symbol': return 0;
case 'undefined': return 0;
case 'object': return 0;
case 'function': return 0;
}
x;
};
20 changes: 20 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofAny.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,20 @@
=== tests/cases/compiler/unreachable.ts ===
const unreachable = (x: any): number => {
>unreachable : Symbol(unreachable, Decl(unreachable.ts, 0, 5))
>x : Symbol(x, Decl(unreachable.ts, 0, 21))

switch (typeof x) {
>x : Symbol(x, Decl(unreachable.ts, 0, 21))

case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
>x : Symbol(x, Decl(unreachable.ts, 0, 21))
}
45 changes: 45 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofAny.types
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,45 @@
=== tests/cases/compiler/unreachable.ts ===
const unreachable = (x: any): number => {
>unreachable : (x: any) => number
>(x: any): number => { switch (typeof x) { case 'string': return 0 case 'number': return 0 case 'bigint': return 0 case 'boolean': return 0 case 'symbol': return 0 case 'undefined': return 0 case 'object': return 0 case 'function': return 0 } x;} : (x: any) => number
>x : any

switch (typeof x) {
>typeof x : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>x : any

case 'string': return 0
>'string' : "string"
>0 : 0

case 'number': return 0
>'number' : "number"
>0 : 0

case 'bigint': return 0
>'bigint' : "bigint"
>0 : 0

case 'boolean': return 0
>'boolean' : "boolean"
>0 : 0

case 'symbol': return 0
>'symbol' : "symbol"
>0 : 0

case 'undefined': return 0
>'undefined' : "undefined"
>0 : 0

case 'object': return 0
>'object' : "object"
>0 : 0

case 'function': return 0
>'function' : "function"
>0 : 0
}
x;
>x : any
}
19 changes: 19 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofUnknown.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,19 @@
tests/cases/compiler/unreachable.ts(12,5): error TS7027: Unreachable code detected.


==== tests/cases/compiler/unreachable.ts (1 errors) ====
const unreachable = (x: unknown): number => {
switch (typeof x) {
case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
~~
!!! error TS7027: Unreachable code detected.
}
29 changes: 29 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofUnknown.js
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,29 @@
//// [unreachable.ts]
const unreachable = (x: unknown): number => {
switch (typeof x) {
case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
}

//// [unreachable.js]
var unreachable = function (x) {
switch (typeof x) {
case 'string': return 0;
case 'number': return 0;
case 'bigint': return 0;
case 'boolean': return 0;
case 'symbol': return 0;
case 'undefined': return 0;
case 'object': return 0;
case 'function': return 0;
}
x;
};
20 changes: 20 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofUnknown.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,20 @@
=== tests/cases/compiler/unreachable.ts ===
const unreachable = (x: unknown): number => {
>unreachable : Symbol(unreachable, Decl(unreachable.ts, 0, 5))
>x : Symbol(x, Decl(unreachable.ts, 0, 21))

switch (typeof x) {
>x : Symbol(x, Decl(unreachable.ts, 0, 21))

case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
>x : Symbol(x, Decl(unreachable.ts, 0, 21))
}
45 changes: 45 additions & 0 deletions tests/baselines/reference/unreachableSwitchTypeofUnknown.types
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,45 @@
=== tests/cases/compiler/unreachable.ts ===
const unreachable = (x: unknown): number => {
>unreachable : (x: unknown) => number
>(x: unknown): number => { switch (typeof x) { case 'string': return 0 case 'number': return 0 case 'bigint': return 0 case 'boolean': return 0 case 'symbol': return 0 case 'undefined': return 0 case 'object': return 0 case 'function': return 0 } x;} : (x: unknown) => number
>x : unknown

switch (typeof x) {
>typeof x : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>x : unknown

case 'string': return 0
>'string' : "string"
>0 : 0

case 'number': return 0
>'number' : "number"
>0 : 0

case 'bigint': return 0
>'bigint' : "bigint"
>0 : 0

case 'boolean': return 0
>'boolean' : "boolean"
>0 : 0

case 'symbol': return 0
>'symbol' : "symbol"
>0 : 0

case 'undefined': return 0
>'undefined' : "undefined"
>0 : 0

case 'object': return 0
>'object' : "object"
>0 : 0

case 'function': return 0
>'function' : "function"
>0 : 0
}
x;
>x : unknown
}
15 changes: 15 additions & 0 deletions tests/cases/compiler/unreachableSwitchTypeofAny.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,15 @@
// @Filename: unreachable.ts
// @allowUnreachableCode: false
const unreachable = (x: any): number => {
switch (typeof x) {
case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
}
15 changes: 15 additions & 0 deletions tests/cases/compiler/unreachableSwitchTypeofUnknown.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,15 @@
// @Filename: unreachable.ts
// @allowUnreachableCode: false
const unreachable = (x: unknown): number => {
switch (typeof x) {
case 'string': return 0
case 'number': return 0
case 'bigint': return 0
case 'boolean': return 0
case 'symbol': return 0
case 'undefined': return 0
case 'object': return 0
case 'function': return 0
}
x;
}