diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index ae13b11389..b68d14ed5e 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -6884,7 +6884,8 @@ namespace ts {
let state = JSDocState.SawAsterisk;
let margin: number | undefined;
// + 4 for leading '/** '
- let indent = start - Math.max(content.lastIndexOf("\n", start), 0) + 4;
+ // + 1 because the last index of \n is always one index before the first character in the line and coincidentally, if there is no \n before start, it is -1, which is also one index before the first character
+ let indent = start - (content.lastIndexOf("\n", start) + 1) + 4;
function pushComment(text: string) {
if (!margin) {
margin = indent;
@@ -6940,7 +6941,7 @@ namespace ts {
comments.push(whitespace);
}
else if (margin !== undefined && indent + whitespace.length > margin) {
- comments.push(whitespace.slice(margin - indent - 1));
+ comments.push(whitespace.slice(margin - indent));
}
indent += whitespace.length;
break;
diff --git a/tests/cases/fourslash/jsDocIndentationPreservation1.ts b/tests/cases/fourslash/jsDocIndentationPreservation1.ts
new file mode 100644
index 0000000000..1e454ac4be
--- /dev/null
+++ b/tests/cases/fourslash/jsDocIndentationPreservation1.ts
@@ -0,0 +1,13 @@
+///
+// @allowJs: true
+// @Filename: Foo.js
+
+/////**
+//// * Does some stuff.
+//// * Second line.
+//// * Third line.
+//// */
+////function foo/**/(){}
+
+goTo.marker();
+verify.quickInfoIs("function foo(): void", "Does some stuff.\n Second line.\n\tThird line.");
diff --git a/tests/cases/fourslash/jsDocIndentationPreservation2.ts b/tests/cases/fourslash/jsDocIndentationPreservation2.ts
new file mode 100644
index 0000000000..e832bc1270
--- /dev/null
+++ b/tests/cases/fourslash/jsDocIndentationPreservation2.ts
@@ -0,0 +1,13 @@
+///
+// @allowJs: true
+// @Filename: Foo.js
+
+/////**
+//// Does some stuff.
+//// Second line.
+//// Third line.
+////*/
+////function foo/**/(){}
+
+goTo.marker();
+verify.quickInfoIs("function foo(): void", "Does some stuff.\n Second line.\n\tThird line.");
diff --git a/tests/cases/fourslash/jsDocIndentationPreservation3.ts b/tests/cases/fourslash/jsDocIndentationPreservation3.ts
new file mode 100644
index 0000000000..117ea0dee4
--- /dev/null
+++ b/tests/cases/fourslash/jsDocIndentationPreservation3.ts
@@ -0,0 +1,13 @@
+///
+// @allowJs: true
+// @Filename: Foo.js
+
+/////**
+//// Does some stuff.
+//// Second line.
+//// Third line.
+////*/
+////function foo/**/(){}
+
+goTo.marker();
+verify.quickInfoIs("function foo(): void", "Does some stuff.\n Second line.\n\tThird line.");