Source Map includes mapping for line ending characters

TypeScript Version: Version 3.8.0-dev.20191023

Search Terms:

source map, source map new line

Code

tsc --inlineSourceMap test.ts

test.ts

console.log('hello');
console.log('world');

test.js

console.log('hello');
console.log('world');
//# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJmaWxlIjoidGVzdC5qcyIsInNvdXJjZVJvb3QiOiIiLCJzb3VyY2VzIjpbInRlc3QudHMiXSwibmFtZXMiOltdLCJtYXBwaW5ncyI6IkFBQUEsT0FBTyxDQUFDLEdBQUcsQ0FBQyxPQUFPLENBQUMsQ0FBQztBQUNyQixPQUFPLENBQUMsR0FBRyxDQUFDLE9BQU8sQ0FBQyxDQUFDIn0=

Source map breaks down into:

"console": test.ts:1:0
".": test.ts:1:7
"log": test.ts:1:8
"(": test.ts:1:11
"'hello'": test.ts:1:12
")": test.ts:1:19
";": test.ts:1:20
"\n": test.ts:1:21  <-- line end
"console": test.ts:2:0
".": test.ts:2:7
"log": test.ts:2:8
"(": test.ts:2:11
"'world'": test.ts:2:12
")": test.ts:2:19
";": test.ts:2:20
"": test.ts:2:21  <-- line end

Expected behavior:

Line end characters left unmapped.

Actual behavior:

Line end characters are included in the mapping, with the column number that equals to the length of the line -- which exceeds the boundary, given that column number is 0-based in a source map.

The spec doesn't cover if mappings for line ending characters should be included. But this behavior breaks some tools (eg. source-map-explorer) with strict boundary checks.

Playground Link:

Related Issues:

Riproduci il problema con tsc --inlineSourceMap test.ts usando il test.ts fornito e ispeziona la source map inline in test.js. Traccia il modo in cui il compilatore registra le mappature alla fine delle righe, quindi verifica che le mappature generate non includano più quei caratteri, mentre le altre mappature rimangano invariate.