fix: correct start of {:else if} and {:else}

.changeset/cold-teachers-turn.md

@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+fix: correct start of `{:else if}` and `{:else}`

packages/svelte/src/compiler/legacy.js

@@ -353,11 +353,12 @@ export function convert(source, ast) {
 					};
 				}
 
+				const start = node.elseif ? node.consequent.nodes[0].start : node.start;
 				remove_surrounding_whitespace_nodes(node.consequent.nodes);
 
 				return {
 					type: 'IfBlock',
-					start: node.start,
+					start,
 					end: node.end,
 					expression: node.test,
 					children: node.consequent.nodes.map(

packages/svelte/src/compiler/phases/1-parse/state/tag.js

@@ -345,7 +345,7 @@ function next(parser) {
 
 			/** @type {ReturnType<typeof parser.append<import('#compiler').IfBlock>>} */
 			const child = parser.append({
-				start: parser.index,
+				start: start - 1,
 				end: -1,
 				type: 'IfBlock',
 				elseif: true,

packages/svelte/tests/parser-modern/samples/if-block-else/input.svelte

@@ -0,0 +1,5 @@
+{#if foo}
+	<p>foo</p>
+{:else}
+	<p>not foo</p>
+{/if}

packages/svelte/tests/parser-modern/samples/if-block-else/output.json

@@ -0,0 +1,116 @@
+{
+	"css": null,
+	"js": [],
+	"start": 0,
+	"end": 51,
+	"type": "Root",
+	"fragment": {
+		"type": "Fragment",
+		"nodes": [
+			{
+				"type": "IfBlock",
+				"elseif": false,
+				"start": 0,
+				"end": 51,
+				"test": {
+					"type": "Identifier",
+					"start": 5,
+					"end": 8,
+					"loc": {
+						"start": {
+							"line": 1,
+							"column": 5
+						},
+						"end": {
+							"line": 1,
+							"column": 8
+						}
+					},
+					"name": "foo"
+				},
+				"consequent": {
+					"type": "Fragment",
+					"nodes": [
+						{
+							"type": "Text",
+							"start": 9,
+							"end": 11,
+							"raw": "\n\t",
+							"data": "\n\t"
+						},
+						{
+							"type": "RegularElement",
+							"start": 11,
+							"end": 21,
+							"name": "p",
+							"attributes": [],
+							"fragment": {
+								"type": "Fragment",
+								"nodes": [
+									{
+										"type": "Text",
+										"start": 14,
+										"end": 17,
+										"raw": "foo",
+										"data": "foo"
+									}
+								],
+								"transparent": true
+							}
+						},
+						{
+							"type": "Text",
+							"start": 21,
+							"end": 22,
+							"raw": "\n",
+							"data": "\n"
+						}
+					],
+					"transparent": false
+				},
+				"alternate": {
+					"type": "Fragment",
+					"nodes": [
+						{
+							"type": "Text",
+							"start": 29,
+							"end": 31,
+							"raw": "\n\t",
+							"data": "\n\t"
+						},
+						{
+							"type": "RegularElement",
+							"start": 31,
+							"end": 45,
+							"name": "p",
+							"attributes": [],
+							"fragment": {
+								"type": "Fragment",
+								"nodes": [
+									{
+										"type": "Text",
+										"start": 34,
+										"end": 41,
+										"raw": "not foo",
+										"data": "not foo"
+									}
+								],
+								"transparent": true
+							}
+						},
+						{
+							"type": "Text",
+							"start": 45,
+							"end": 46,
+							"raw": "\n",
+							"data": "\n"
+						}
+					],
+					"transparent": false
+				}
+			}
+		],
+		"transparent": false
+	},
+	"options": null
+}

packages/svelte/tests/parser-modern/samples/if-block-elseif/input.svelte

@@ -0,0 +1,5 @@
+{#if x > 10}
+	<p>x is greater than 10</p>
+{:else if x < 5}
+	<p>x is less than 5</p>
+{/if}

packages/svelte/tests/parser-modern/samples/if-block-elseif/output.json

@@ -0,0 +1,211 @@
+{
+	"css": null,
+	"js": [],
+	"start": 0,
+	"end": 89,
+	"type": "Root",
+	"fragment": {
+		"type": "Fragment",
+		"nodes": [
+			{
+				"type": "IfBlock",
+				"elseif": false,
+				"start": 0,
+				"end": 89,
+				"test": {
+					"type": "BinaryExpression",
+					"start": 5,
+					"end": 11,
+					"loc": {
+						"start": {
+							"line": 1,
+							"column": 5
+						},
+						"end": {
+							"line": 1,
+							"column": 11
+						}
+					},
+					"left": {
+						"type": "Identifier",
+						"start": 5,
+						"end": 6,
+						"loc": {
+							"start": {
+								"line": 1,
+								"column": 5
+							},
+							"end": {
+								"line": 1,
+								"column": 6
+							}
+						},
+						"name": "x"
+					},
+					"operator": ">",
+					"right": {
+						"type": "Literal",
+						"start": 9,
+						"end": 11,
+						"loc": {
+							"start": {
+								"line": 1,
+								"column": 9
+							},
+							"end": {
+								"line": 1,
+								"column": 11
+							}
+						},
+						"value": 10,
+						"raw": "10"
+					}
+				},
+				"consequent": {
+					"type": "Fragment",
+					"nodes": [
+						{
+							"type": "Text",
+							"start": 12,
+							"end": 14,
+							"raw": "\n\t",
+							"data": "\n\t"
+						},
+						{
+							"type": "RegularElement",
+							"start": 14,
+							"end": 41,
+							"name": "p",
+							"attributes": [],
+							"fragment": {
+								"type": "Fragment",
+								"nodes": [
+									{
+										"type": "Text",
+										"start": 17,
+										"end": 37,
+										"raw": "x is greater than 10",
+										"data": "x is greater than 10"
+									}
+								],
+								"transparent": true
+							}
+						},
+						{
+							"type": "Text",
+							"start": 41,
+							"end": 42,
+							"raw": "\n",
+							"data": "\n"
+						}
+					],
+					"transparent": false
+				},
+				"alternate": {
+					"type": "Fragment",
+					"nodes": [
+						{
+							"start": 42,
+							"end": 89,
+							"type": "IfBlock",
+							"elseif": true,
+							"test": {
+								"type": "BinaryExpression",
+								"start": 52,
+								"end": 57,
+								"loc": {
+									"start": {
+										"line": 3,
+										"column": 10
+									},
+									"end": {
+										"line": 3,
+										"column": 15
+									}
+								},
+								"left": {
+									"type": "Identifier",
+									"start": 52,
+									"end": 53,
+									"loc": {
+										"start": {
+											"line": 3,
+											"column": 10
+										},
+										"end": {
+											"line": 3,
+											"column": 11
+										}
+									},
+									"name": "x"
+								},
+								"operator": "<",
+								"right": {
+									"type": "Literal",
+									"start": 56,
+									"end": 57,
+									"loc": {
+										"start": {
+											"line": 3,
+											"column": 14
+										},
+										"end": {
+											"line": 3,
+											"column": 15
+										}
+									},
+									"value": 5,
+									"raw": "5"
+								}
+							},
+							"consequent": {
+								"type": "Fragment",
+								"nodes": [
+									{
+										"type": "Text",
+										"start": 58,
+										"end": 60,
+										"raw": "\n\t",
+										"data": "\n\t"
+									},
+									{
+										"type": "RegularElement",
+										"start": 60,
+										"end": 83,
+										"name": "p",
+										"attributes": [],
+										"fragment": {
+											"type": "Fragment",
+											"nodes": [
+												{
+													"type": "Text",
+													"start": 63,
+													"end": 79,
+													"raw": "x is less than 5",
+													"data": "x is less than 5"
+												}
+											],
+											"transparent": true
+										}
+									},
+									{
+										"type": "Text",
+										"start": 83,
+										"end": 84,
+										"raw": "\n",
+										"data": "\n"
+									}
+								],
+								"transparent": false
+							},
+							"alternate": null
+						}
+					],
+					"transparent": false
+				}
+			}
+		],
+		"transparent": false
+	},
+	"options": null
+}

packages/svelte/tests/parser-modern/samples/if-block/input.svelte

@@ -0,0 +1 @@
+{#if foo}bar{/if}