Merge consecutive text nodes when inspecting markdown (#9112)

* Fix assertion order

expected/actual were in wrong order, resulting in misleading output in
case of failing tests

* Merge consesutive markdown text nodes

This ensures that parser quirks such as "hello!" being parsed as
two separate nodes ("hello" and "!") are not exposed to code inspecting
a markdown strings.

3 files changed, 57 insertions, 23 deletions

diff --git a/utils/markdown/inlines.go b/utils/markdown/inlines.go
index 8a4f7a531..02ef47e24 100644
--- a/utils/markdown/inlines.go
+++ b/utils/markdown/inlines.go
@@ -476,6 +476,40 @@ func ParseInlines(markdown string, ranges []Range, referenceDefinitions []*Refer
 	return newInlineParser(markdown, ranges, referenceDefinitions).Parse()
 }
 
+func MergeInlineText(inlines []Inline) []Inline {
+	var ret []Inline
+	for i, v := range inlines {
+		// always add first node
+		if i == 0 {
+			ret = append(ret, v)
+			continue
+		}
+		// not a text node? nothing to merge
+		text, ok := v.(*Text)
+		if !ok {
+			ret = append(ret, v)
+			continue
+		}
+		// previous node is not a text node? nothing to merge
+		prevText, ok := ret[len(ret)-1].(*Text)
+		if !ok {
+			ret = append(ret, v)
+			continue
+		}
+		// previous node is not right before this one
+		if prevText.Range.End != text.Range.Position {
+			ret = append(ret, v)
+			continue
+		}
+		// we have two consecutive text nodes
+		ret[len(ret)-1] = &Text{
+			Text:  prevText.Text + text.Text,
+			Range: Range{prevText.Range.Position, text.Range.End},
+		}
+	}
+	return ret
+}
+
 func Unescape(markdown string) string {
 	ret := ""
 
diff --git a/utils/markdown/inspect.go b/utils/markdown/inspect.go
index c4e3bf1ac..80b5bc246 100644
--- a/utils/markdown/inspect.go
+++ b/utils/markdown/inspect.go
@@ -13,7 +13,7 @@ func Inspect(markdown string, f func(interface{}) bool) {
 		}
 		switch v := block.(type) {
 		case *Paragraph:
-			for _, inline := range v.ParseInlines(referenceDefinitions) {
+			for _, inline := range MergeInlineText(v.ParseInlines(referenceDefinitions)) {
 				InspectInline(inline, func(inline Inline) bool {
 					return f(inline)
 				})
diff --git a/utils/markdown/text_range_test.go b/utils/markdown/text_range_test.go
index 9c0efea85..25c13c40d 100644
--- a/utils/markdown/text_range_test.go
+++ b/utils/markdown/text_range_test.go
@@ -22,8 +22,8 @@ func TestTextRanges(t *testing.T) {
 		},
 		"simple2": {
 			Markdown:       "hello!",
-			ExpectedRanges: []Range{{0, 5}, {5, 6}},
-			ExpectedValues: []string{"hello", "!"},
+			ExpectedRanges: []Range{{0, 6}},
+			ExpectedValues: []string{"hello!"},
 		},
 		"multiline": {
 			Markdown:       "hello world\nfoobar",
@@ -37,13 +37,13 @@ func TestTextRanges(t *testing.T) {
 		},
 		"notcode": {
 			Markdown:       "hello ` world",
-			ExpectedRanges: []Range{{0, 6}, {6, 7}, {7, 13}},
-			ExpectedValues: []string{"hello ", "`", " world"},
+			ExpectedRanges: []Range{{0, 13}},
+			ExpectedValues: []string{"hello ` world"},
 		},
 		"escape": {
 			Markdown:       "\\*hello\\*",
-			ExpectedRanges: []Range{{1, 2}, {2, 7}, {8, 9}},
-			ExpectedValues: []string{"*", "hello", "*"},
+			ExpectedRanges: []Range{{1, 7}, {8, 9}},
+			ExpectedValues: []string{"*hello", "*"},
 		},
 		"escapeescape": {
 			Markdown:       "\\\\",
@@ -52,28 +52,28 @@ func TestTextRanges(t *testing.T) {
 		},
 		"notescape": {
 			Markdown:       "foo\\x",
-			ExpectedRanges: []Range{{0, 3}, {3, 4}, {4, 5}},
-			ExpectedValues: []string{"foo", "\\", "x"},
+			ExpectedRanges: []Range{{0, 5}},
+			ExpectedValues: []string{"foo\\x"},
 		},
 		"notlink": {
 			Markdown:       "[foo",
-			ExpectedRanges: []Range{{0, 1}, {1, 4}},
-			ExpectedValues: []string{"[", "foo"},
+			ExpectedRanges: []Range{{0, 4}},
+			ExpectedValues: []string{"[foo"},
 		},
 		"notlinkend": {
 			Markdown:       "[foo]",
-			ExpectedRanges: []Range{{0, 1}, {1, 4}, {4, 5}},
-			ExpectedValues: []string{"[", "foo", "]"},
+			ExpectedRanges: []Range{{0, 5}},
+			ExpectedValues: []string{"[foo]"},
 		},
 		"notimage": {
 			Markdown:       "![foo",
-			ExpectedRanges: []Range{{0, 2}, {2, 5}},
-			ExpectedValues: []string{"![", "foo"},
+			ExpectedRanges: []Range{{0, 5}},
+			ExpectedValues: []string{"![foo"},
 		},
 		"notimage2": {
 			Markdown:       "!foo",
-			ExpectedRanges: []Range{{0, 1}, {1, 4}},
-			ExpectedValues: []string{"!", "foo"},
+			ExpectedRanges: []Range{{0, 4}},
+			ExpectedValues: []string{"!foo"},
 		},
 		"charref": {
 			Markdown:       ""test",
@@ -82,13 +82,13 @@ func TestTextRanges(t *testing.T) {
 		},
 		"notcharref": {
 			Markdown:       "&amp test",
-			ExpectedRanges: []Range{{0, 1}, {1, 9}},
-			ExpectedValues: []string{"&", "amp test"},
+			ExpectedRanges: []Range{{0, 9}},
+			ExpectedValues: []string{"&amp test"},
 		},
 		"notcharref2": {
 			Markdown:       "&mattermost;",
-			ExpectedRanges: []Range{{0, 1}, {1, 12}},
-			ExpectedValues: []string{"&", "mattermost;"},
+			ExpectedRanges: []Range{{0, 12}},
+			ExpectedValues: []string{"&mattermost;"},
 		},
 	} {
 		t.Run(name, func(t *testing.T) {
@@ -101,8 +101,8 @@ func TestTextRanges(t *testing.T) {
 				}
 				return true
 			})
-			assert.Equal(t, ranges, tc.ExpectedRanges)
-			assert.Equal(t, values, tc.ExpectedValues)
+			assert.Equal(t, tc.ExpectedRanges, ranges)
+			assert.Equal(t, tc.ExpectedValues, values)
 
 		})
 	}