Merge pull request #2982 from ehuss/fix-sidebar-scroll

Fix sidebar scroll position when heading nav is involved

crates/mdbook-html/front-end/templates/toc.js.hbs

@@ -40,14 +40,22 @@ class MDBookSidebarScrollbox extends HTMLElement {
         // Track and set sidebar scroll position
         this.addEventListener('click', e => {
             if (e.target.tagName === 'A') {
-                sessionStorage.setItem('sidebar-scroll', this.scrollTop);
+                const clientRect = e.target.getBoundingClientRect();
+                const sidebarRect = this.getBoundingClientRect();
+                sessionStorage.setItem('sidebar-scroll-offset', clientRect.top - sidebarRect.top);
             }
         }, { passive: true });
-        const sidebarScrollTop = sessionStorage.getItem('sidebar-scroll');
+        const sidebarScrollOffset = sessionStorage.getItem('sidebar-scroll-offset');
-        sessionStorage.removeItem('sidebar-scroll');
+        sessionStorage.removeItem('sidebar-scroll-offset');
-        if (sidebarScrollTop) {
+        if (sidebarScrollOffset !== null) {
             // preserve sidebar scroll position when navigating via links within sidebar
-            this.scrollTop = sidebarScrollTop;
+            const activeSection = this.querySelector('.active');
+            if (activeSection) {
+                const clientRect = activeSection.getBoundingClientRect();
+                const sidebarRect = this.getBoundingClientRect();
+                const currentOffset = clientRect.top - sidebarRect.top;
+                this.scrollTop += currentOffset - parseFloat(sidebarScrollOffset);
+            }
         } else {
             // scroll sidebar to current active section when navigating via
             // 'next/previous chapter' buttons

tests/gui/books/sidebar-scroll/book.toml

@@ -0,0 +1,3 @@
+[book]
+title = "sidebar-scroll"
+language = "en"

tests/gui/books/sidebar-scroll/src/SUMMARY.md

@@ -0,0 +1,102 @@
+# Summary
+
+- [Chapter 1](./chapter_1.md)
+- [Chapter 2](./chapter_2.md)
+- [Chapter 3](./chapter_3.md)
+- [Chapter 4](./chapter_4.md)
+- [Chapter 5](./chapter_5.md)
+- [Chapter 6](./chapter_6.md)
+- [Chapter 7](./chapter_7.md)
+- [Chapter 8](./chapter_8.md)
+- [Chapter 9](./chapter_9.md)
+- [Chapter 10](./chapter_10.md)
+- [Chapter 11](./chapter_11.md)
+- [Chapter 12](./chapter_12.md)
+- [Chapter 13](./chapter_13.md)
+- [Chapter 14](./chapter_14.md)
+- [Chapter 15](./chapter_15.md)
+- [Chapter 16](./chapter_16.md)
+- [Chapter 17](./chapter_17.md)
+- [Chapter 18](./chapter_18.md)
+- [Chapter 19](./chapter_19.md)
+- [Chapter 20](./chapter_20.md)
+- [Chapter 21](./chapter_21.md)
+- [Chapter 22](./chapter_22.md)
+- [Chapter 23](./chapter_23.md)
+- [Chapter 24](./chapter_24.md)
+- [Chapter 25](./chapter_25.md)
+- [Chapter 26](./chapter_26.md)
+- [Chapter 27](./chapter_27.md)
+- [Chapter 28](./chapter_28.md)
+- [Chapter 29](./chapter_29.md)
+- [Chapter 30](./chapter_30.md)
+- [Chapter 31](./chapter_31.md)
+- [Chapter 32](./chapter_32.md)
+- [Chapter 33](./chapter_33.md)
+- [Chapter 34](./chapter_34.md)
+- [Chapter 35](./chapter_35.md)
+- [Chapter 36](./chapter_36.md)
+- [Chapter 37](./chapter_37.md)
+- [Chapter 38](./chapter_38.md)
+- [Chapter 39](./chapter_39.md)
+- [Chapter 40](./chapter_40.md)
+- [Chapter 41](./chapter_41.md)
+- [Chapter 42](./chapter_42.md)
+- [Chapter 43](./chapter_43.md)
+- [Chapter 44](./chapter_44.md)
+- [Chapter 45](./chapter_45.md)
+- [Chapter 46](./chapter_46.md)
+- [Chapter 47](./chapter_47.md)
+- [Chapter 48](./chapter_48.md)
+- [Chapter 49](./chapter_49.md)
+- [Chapter 50](./chapter_50.md)
+- [Chapter 51](./chapter_51.md)
+- [Chapter 52](./chapter_52.md)
+- [Chapter 53](./chapter_53.md)
+- [Chapter 54](./chapter_54.md)
+- [Chapter 55](./chapter_55.md)
+- [Chapter 56](./chapter_56.md)
+- [Chapter 57](./chapter_57.md)
+- [Chapter 58](./chapter_58.md)
+- [Chapter 59](./chapter_59.md)
+- [Chapter 60](./chapter_60.md)
+- [Chapter 61](./chapter_61.md)
+- [Chapter 62](./chapter_62.md)
+- [Chapter 63](./chapter_63.md)
+- [Chapter 64](./chapter_64.md)
+- [Chapter 65](./chapter_65.md)
+- [Chapter 66](./chapter_66.md)
+- [Chapter 67](./chapter_67.md)
+- [Chapter 68](./chapter_68.md)
+- [Chapter 69](./chapter_69.md)
+- [Chapter 70](./chapter_70.md)
+- [Chapter 71](./chapter_71.md)
+- [Chapter 72](./chapter_72.md)
+- [Chapter 73](./chapter_73.md)
+- [Chapter 74](./chapter_74.md)
+- [Chapter 75](./chapter_75.md)
+- [Chapter 76](./chapter_76.md)
+- [Chapter 77](./chapter_77.md)
+- [Chapter 78](./chapter_78.md)
+- [Chapter 79](./chapter_79.md)
+- [Chapter 80](./chapter_80.md)
+- [Chapter 81](./chapter_81.md)
+- [Chapter 82](./chapter_82.md)
+- [Chapter 83](./chapter_83.md)
+- [Chapter 84](./chapter_84.md)
+- [Chapter 85](./chapter_85.md)
+- [Chapter 86](./chapter_86.md)
+- [Chapter 87](./chapter_87.md)
+- [Chapter 88](./chapter_88.md)
+- [Chapter 89](./chapter_89.md)
+- [Chapter 90](./chapter_90.md)
+- [Chapter 91](./chapter_91.md)
+- [Chapter 92](./chapter_92.md)
+- [Chapter 93](./chapter_93.md)
+- [Chapter 94](./chapter_94.md)
+- [Chapter 95](./chapter_95.md)
+- [Chapter 96](./chapter_96.md)
+- [Chapter 97](./chapter_97.md)
+- [Chapter 98](./chapter_98.md)
+- [Chapter 99](./chapter_99.md)
+- [Chapter 100](./chapter_100.md)

tests/gui/books/sidebar-scroll/src/chapter_1.md

@@ -0,0 +1,3 @@
+# Chapter 1
+
+## This has a single heading

tests/gui/books/sidebar-scroll/src/chapter_10.md

@@ -0,0 +1,28 @@
+# Chapter 10
+
+## Heading A
+## Heading B
+## Heading C
+## Heading D
+## Heading E
+## Heading F
+## Heading G
+## Heading H
+## Heading I
+## Heading J
+## Heading K
+## Heading L
+## Heading M
+## Heading N
+## Heading O
+## Heading P
+## Heading Q
+## Heading R
+## Heading S
+## Heading T
+## Heading U
+## Heading V
+## Heading W
+## Heading X
+## Heading Y
+## Heading Z

tests/gui/books/sidebar-scroll/src/chapter_100.md

@@ -0,0 +1 @@
+# Chapter 100

tests/gui/books/sidebar-scroll/src/chapter_11.md

@@ -0,0 +1 @@
+# Chapter 11

tests/gui/books/sidebar-scroll/src/chapter_12.md

@@ -0,0 +1 @@
+# Chapter 12

tests/gui/books/sidebar-scroll/src/chapter_13.md

@@ -0,0 +1 @@
+# Chapter 13

tests/gui/books/sidebar-scroll/src/chapter_14.md

@@ -0,0 +1 @@
+# Chapter 14

tests/gui/books/sidebar-scroll/src/chapter_15.md

@@ -0,0 +1 @@
+# Chapter 15

tests/gui/books/sidebar-scroll/src/chapter_16.md

@@ -0,0 +1 @@
+# Chapter 16

tests/gui/books/sidebar-scroll/src/chapter_17.md

@@ -0,0 +1 @@
+# Chapter 17

tests/gui/books/sidebar-scroll/src/chapter_18.md

@@ -0,0 +1 @@
+# Chapter 18

tests/gui/books/sidebar-scroll/src/chapter_19.md

@@ -0,0 +1 @@
+# Chapter 19

tests/gui/books/sidebar-scroll/src/chapter_2.md

@@ -0,0 +1 @@
+# Chapter 2

tests/gui/books/sidebar-scroll/src/chapter_20.md

@@ -0,0 +1 @@
+# Chapter 20

tests/gui/books/sidebar-scroll/src/chapter_21.md

@@ -0,0 +1 @@
+# Chapter 21

tests/gui/books/sidebar-scroll/src/chapter_22.md

@@ -0,0 +1 @@
+# Chapter 22

tests/gui/books/sidebar-scroll/src/chapter_23.md

@@ -0,0 +1 @@
+# Chapter 23

tests/gui/books/sidebar-scroll/src/chapter_24.md

@@ -0,0 +1 @@
+# Chapter 24

tests/gui/books/sidebar-scroll/src/chapter_25.md

@@ -0,0 +1 @@
+# Chapter 25

tests/gui/books/sidebar-scroll/src/chapter_26.md

@@ -0,0 +1 @@
+# Chapter 26

tests/gui/books/sidebar-scroll/src/chapter_27.md

@@ -0,0 +1 @@
+# Chapter 27

tests/gui/books/sidebar-scroll/src/chapter_28.md

@@ -0,0 +1 @@
+# Chapter 28

tests/gui/books/sidebar-scroll/src/chapter_29.md

@@ -0,0 +1 @@
+# Chapter 29

tests/gui/books/sidebar-scroll/src/chapter_3.md

@@ -0,0 +1 @@
+# Chapter 3

tests/gui/books/sidebar-scroll/src/chapter_30.md

@@ -0,0 +1 @@
+# Chapter 30

tests/gui/books/sidebar-scroll/src/chapter_31.md

@@ -0,0 +1 @@
+# Chapter 31

tests/gui/books/sidebar-scroll/src/chapter_32.md

@@ -0,0 +1 @@
+# Chapter 32

tests/gui/books/sidebar-scroll/src/chapter_33.md

@@ -0,0 +1 @@
+# Chapter 33

tests/gui/books/sidebar-scroll/src/chapter_34.md

@@ -0,0 +1 @@
+# Chapter 34

tests/gui/books/sidebar-scroll/src/chapter_35.md

@@ -0,0 +1,28 @@
+# Chapter 35
+
+## Heading A
+## Heading B
+## Heading C
+## Heading D
+## Heading E
+## Heading F
+## Heading G
+## Heading H
+## Heading I
+## Heading J
+## Heading K
+## Heading L
+## Heading M
+## Heading N
+## Heading O
+## Heading P
+## Heading Q
+## Heading R
+## Heading S
+## Heading T
+## Heading U
+## Heading V
+## Heading W
+## Heading X
+## Heading Y
+## Heading Z

tests/gui/books/sidebar-scroll/src/chapter_36.md

@@ -0,0 +1 @@
+# Chapter 36

tests/gui/books/sidebar-scroll/src/chapter_37.md

@@ -0,0 +1 @@
+# Chapter 37

tests/gui/books/sidebar-scroll/src/chapter_38.md

@@ -0,0 +1 @@
+# Chapter 38

tests/gui/books/sidebar-scroll/src/chapter_39.md

@@ -0,0 +1 @@
+# Chapter 39

tests/gui/books/sidebar-scroll/src/chapter_4.md

@@ -0,0 +1 @@
+# Chapter 4

tests/gui/books/sidebar-scroll/src/chapter_40.md

@@ -0,0 +1 @@
+# Chapter 40

tests/gui/books/sidebar-scroll/src/chapter_41.md

@@ -0,0 +1 @@
+# Chapter 41

tests/gui/books/sidebar-scroll/src/chapter_42.md

@@ -0,0 +1 @@
+# Chapter 42

tests/gui/books/sidebar-scroll/src/chapter_43.md

@@ -0,0 +1 @@
+# Chapter 43

tests/gui/books/sidebar-scroll/src/chapter_44.md

@@ -0,0 +1 @@
+# Chapter 44

tests/gui/books/sidebar-scroll/src/chapter_45.md

@@ -0,0 +1 @@
+# Chapter 45

tests/gui/books/sidebar-scroll/src/chapter_46.md

@@ -0,0 +1 @@
+# Chapter 46

tests/gui/books/sidebar-scroll/src/chapter_47.md

@@ -0,0 +1 @@
+# Chapter 47

tests/gui/books/sidebar-scroll/src/chapter_48.md

@@ -0,0 +1 @@
+# Chapter 48

tests/gui/books/sidebar-scroll/src/chapter_49.md

@@ -0,0 +1 @@
+# Chapter 49

tests/gui/books/sidebar-scroll/src/chapter_5.md

@@ -0,0 +1 @@
+# Chapter 5

tests/gui/books/sidebar-scroll/src/chapter_50.md

@@ -0,0 +1 @@
+# Chapter 50

tests/gui/books/sidebar-scroll/src/chapter_51.md

@@ -0,0 +1 @@
+# Chapter 51

tests/gui/books/sidebar-scroll/src/chapter_52.md

@@ -0,0 +1 @@
+# Chapter 52

tests/gui/books/sidebar-scroll/src/chapter_53.md

@@ -0,0 +1 @@
+# Chapter 53

tests/gui/books/sidebar-scroll/src/chapter_54.md

@@ -0,0 +1 @@
+# Chapter 54

tests/gui/books/sidebar-scroll/src/chapter_55.md

@@ -0,0 +1 @@
+# Chapter 55

tests/gui/books/sidebar-scroll/src/chapter_56.md

@@ -0,0 +1 @@
+# Chapter 56

tests/gui/books/sidebar-scroll/src/chapter_57.md

@@ -0,0 +1 @@
+# Chapter 57

tests/gui/books/sidebar-scroll/src/chapter_58.md

@@ -0,0 +1 @@
+# Chapter 58

tests/gui/books/sidebar-scroll/src/chapter_59.md

@@ -0,0 +1 @@
+# Chapter 59

tests/gui/books/sidebar-scroll/src/chapter_6.md

@@ -0,0 +1 @@
+# Chapter 6

tests/gui/books/sidebar-scroll/src/chapter_60.md

@@ -0,0 +1 @@
+# Chapter 60

tests/gui/books/sidebar-scroll/src/chapter_61.md

@@ -0,0 +1 @@
+# Chapter 61

tests/gui/books/sidebar-scroll/src/chapter_62.md

@@ -0,0 +1 @@
+# Chapter 62

tests/gui/books/sidebar-scroll/src/chapter_63.md

@@ -0,0 +1 @@
+# Chapter 63

tests/gui/books/sidebar-scroll/src/chapter_64.md

@@ -0,0 +1 @@
+# Chapter 64

tests/gui/books/sidebar-scroll/src/chapter_65.md

@@ -0,0 +1 @@
+# Chapter 65

tests/gui/books/sidebar-scroll/src/chapter_66.md

@@ -0,0 +1 @@
+# Chapter 66

tests/gui/books/sidebar-scroll/src/chapter_67.md

@@ -0,0 +1 @@
+# Chapter 67

tests/gui/books/sidebar-scroll/src/chapter_68.md

@@ -0,0 +1 @@
+# Chapter 68

tests/gui/books/sidebar-scroll/src/chapter_69.md

@@ -0,0 +1 @@
+# Chapter 69

tests/gui/books/sidebar-scroll/src/chapter_7.md

@@ -0,0 +1 @@
+# Chapter 7

tests/gui/books/sidebar-scroll/src/chapter_70.md

@@ -0,0 +1 @@
+# Chapter 70

tests/gui/books/sidebar-scroll/src/chapter_71.md

@@ -0,0 +1 @@
+# Chapter 71

tests/gui/books/sidebar-scroll/src/chapter_72.md

@@ -0,0 +1 @@
+# Chapter 72

tests/gui/books/sidebar-scroll/src/chapter_73.md

@@ -0,0 +1 @@
+# Chapter 73

tests/gui/books/sidebar-scroll/src/chapter_74.md

@@ -0,0 +1 @@
+# Chapter 74

tests/gui/books/sidebar-scroll/src/chapter_75.md

@@ -0,0 +1 @@
+# Chapter 75

tests/gui/books/sidebar-scroll/src/chapter_76.md

@@ -0,0 +1 @@
+# Chapter 76

tests/gui/books/sidebar-scroll/src/chapter_77.md

@@ -0,0 +1 @@
+# Chapter 77

tests/gui/books/sidebar-scroll/src/chapter_78.md

@@ -0,0 +1 @@
+# Chapter 78

tests/gui/books/sidebar-scroll/src/chapter_79.md

@@ -0,0 +1 @@
+# Chapter 79

tests/gui/books/sidebar-scroll/src/chapter_8.md

@@ -0,0 +1 @@
+# Chapter 8

tests/gui/books/sidebar-scroll/src/chapter_80.md

@@ -0,0 +1 @@
+# Chapter 80

tests/gui/books/sidebar-scroll/src/chapter_81.md

@@ -0,0 +1 @@
+# Chapter 81

tests/gui/books/sidebar-scroll/src/chapter_82.md

@@ -0,0 +1 @@
+# Chapter 82

tests/gui/books/sidebar-scroll/src/chapter_83.md

@@ -0,0 +1 @@
+# Chapter 83

tests/gui/books/sidebar-scroll/src/chapter_84.md

@@ -0,0 +1 @@
+# Chapter 84

tests/gui/books/sidebar-scroll/src/chapter_85.md

@@ -0,0 +1 @@
+# Chapter 85

tests/gui/books/sidebar-scroll/src/chapter_86.md

@@ -0,0 +1 @@
+# Chapter 86

tests/gui/books/sidebar-scroll/src/chapter_87.md

@@ -0,0 +1 @@
+# Chapter 87

tests/gui/books/sidebar-scroll/src/chapter_88.md

@@ -0,0 +1 @@
+# Chapter 88

tests/gui/books/sidebar-scroll/src/chapter_89.md

@@ -0,0 +1 @@
+# Chapter 89

tests/gui/books/sidebar-scroll/src/chapter_9.md

@@ -0,0 +1 @@
+# Chapter 9

tests/gui/books/sidebar-scroll/src/chapter_90.md

@@ -0,0 +1 @@
+# Chapter 90

tests/gui/books/sidebar-scroll/src/chapter_91.md

@@ -0,0 +1 @@
+# Chapter 91

tests/gui/books/sidebar-scroll/src/chapter_92.md

@@ -0,0 +1 @@
+# Chapter 92

tests/gui/books/sidebar-scroll/src/chapter_93.md

@@ -0,0 +1 @@
+# Chapter 93

tests/gui/books/sidebar-scroll/src/chapter_94.md

@@ -0,0 +1 @@
+# Chapter 94

tests/gui/books/sidebar-scroll/src/chapter_95.md

@@ -0,0 +1 @@
+# Chapter 95

tests/gui/books/sidebar-scroll/src/chapter_96.md

@@ -0,0 +1 @@
+# Chapter 96