Improve issue autolinks (#6273)

* Improve issue autolinks

Update autolinks to match what github does here:

Issue in same repo: #1
Issue in different repo: org/repo#1

Fixes #6264

* Use setting.AppURL when parsing URL

Using setting.AppURL here is a more reliable way of parsing the current
URL and what other functions in this file seem to use.

* Make ComposeMetas always return a valid context

* Add per repository markdown renderers for better context

* Update for use of context metas

Now that we include the user and repo name inside context metas, update
various code and tests for this new logic

3 files changed, 52 insertions, 16 deletions

diff --git a/modules/markup/html.go b/modules/markup/html.go
index 136f76d301..930c6b3a3e 100644
--- a/modules/markup/html.go
+++ b/modules/markup/html.go
@@ -551,20 +551,37 @@ func shortLinkProcessorFull(ctx *postProcessCtx, node *html.Node, noLink bool) {
 }
 
 func fullIssuePatternProcessor(ctx *postProcessCtx, node *html.Node) {
+	if ctx.metas == nil {
+		return
+	}
 	m := getIssueFullPattern().FindStringSubmatchIndex(node.Data)
 	if m == nil {
 		return
 	}
 	link := node.Data[m[0]:m[1]]
 	id := "#" + node.Data[m[2]:m[3]]
-	// TODO if m[4]:m[5] is not nil, then link is to a comment,
-	// and we should indicate that in the text somehow
-	replaceContent(node, m[0], m[1], createLink(link, id))
+
+	// extract repo and org name from matched link like
+	// http://localhost:3000/gituser/myrepo/issues/1
+	linkParts := strings.Split(path.Clean(link), "/")
+	matchOrg := linkParts[len(linkParts)-4]
+	matchRepo := linkParts[len(linkParts)-3]
+
+	if matchOrg == ctx.metas["user"] && matchRepo == ctx.metas["repo"] {
+		// TODO if m[4]:m[5] is not nil, then link is to a comment,
+		// and we should indicate that in the text somehow
+		replaceContent(node, m[0], m[1], createLink(link, id))
+
+	} else {
+		orgRepoID := matchOrg + "/" + matchRepo + id
+		replaceContent(node, m[0], m[1], createLink(link, orgRepoID))
+	}
 }
 
 func issueIndexPatternProcessor(ctx *postProcessCtx, node *html.Node) {
-	prefix := cutoutVerbosePrefix(ctx.urlPrefix)
-
+	if ctx.metas == nil {
+		return
+	}
 	// default to numeric pattern, unless alphanumeric is requested.
 	pattern := issueNumericPattern
 	if ctx.metas["style"] == IssueNameStyleAlphanumeric {
@@ -575,11 +592,10 @@ func issueIndexPatternProcessor(ctx *postProcessCtx, node *html.Node) {
 	if match == nil {
 		return
 	}
+
 	id := node.Data[match[2]:match[3]]
 	var link *html.Node
-	if ctx.metas == nil {
-		link = createLink(util.URLJoin(prefix, "issues", id[1:]), id)
-	} else {
+	if _, ok := ctx.metas["format"]; ok {
 		// Support for external issue tracker
 		if ctx.metas["style"] == IssueNameStyleAlphanumeric {
 			ctx.metas["index"] = id
@@ -587,6 +603,8 @@ func issueIndexPatternProcessor(ctx *postProcessCtx, node *html.Node) {
 			ctx.metas["index"] = id[1:]
 		}
 		link = createLink(com.Expand(ctx.metas["format"], ctx.metas), id)
+	} else {
+		link = createLink(util.URLJoin(setting.AppURL, ctx.metas["user"], ctx.metas["repo"], "issues", id[1:]), id)
 	}
 	replaceContent(node, match[2], match[3], link)
 }
diff --git a/modules/markup/html_internal_test.go b/modules/markup/html_internal_test.go
index c71948593d..135a8e103c 100644
--- a/modules/markup/html_internal_test.go
+++ b/modules/markup/html_internal_test.go
@@ -53,6 +53,12 @@ var alphanumericMetas = map[string]string{
 	"style":  IssueNameStyleAlphanumeric,
 }
 
+// these values should match the Repo const above
+var localMetas = map[string]string{
+	"user": "gogits",
+	"repo": "gogs",
+}
+
 func TestRender_IssueIndexPattern(t *testing.T) {
 	// numeric: render inputs without valid mentions
 	test := func(s string) {
@@ -91,7 +97,7 @@ func TestRender_IssueIndexPattern2(t *testing.T) {
 			links[i] = numericIssueLink(util.URLJoin(setting.AppSubURL, "issues"), index)
 		}
 		expectedNil := fmt.Sprintf(expectedFmt, links...)
-		testRenderIssueIndexPattern(t, s, expectedNil, nil)
+		testRenderIssueIndexPattern(t, s, expectedNil, &postProcessCtx{metas: localMetas})
 
 		for i, index := range indices {
 			links[i] = numericIssueLink("https://someurl.com/someUser/someRepo/", index)
@@ -171,6 +177,7 @@ func testRenderIssueIndexPattern(t *testing.T, input, expected string, ctx *post
 	if ctx.urlPrefix == "" {
 		ctx.urlPrefix = AppSubURL
 	}
+
 	res, err := ctx.postProcess([]byte(input))
 	assert.NoError(t, err)
 	assert.Equal(t, expected, string(res))
@@ -181,10 +188,10 @@ func TestRender_AutoLink(t *testing.T) {
 	setting.AppSubURL = AppSubURL
 
 	test := func(input, expected string) {
-		buffer, err := PostProcess([]byte(input), setting.AppSubURL, nil, false)
+		buffer, err := PostProcess([]byte(input), setting.AppSubURL, localMetas, false)
 		assert.Equal(t, err, nil)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(string(buffer)))
-		buffer, err = PostProcess([]byte(input), setting.AppSubURL, nil, true)
+		buffer, err = PostProcess([]byte(input), setting.AppSubURL, localMetas, true)
 		assert.Equal(t, err, nil)
 		assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(string(buffer)))
 	}
@@ -214,6 +221,7 @@ func TestRender_FullIssueURLs(t *testing.T) {
 		if ctx.urlPrefix == "" {
 			ctx.urlPrefix = AppSubURL
 		}
+		ctx.metas = localMetas
 		result, err := ctx.postProcess([]byte(input))
 		assert.NoError(t, err)
 		assert.Equal(t, expected, string(result))
@@ -221,9 +229,11 @@ func TestRender_FullIssueURLs(t *testing.T) {
 	test("Here is a link https://git.osgeo.org/gogs/postgis/postgis/pulls/6",
 		"Here is a link https://git.osgeo.org/gogs/postgis/postgis/pulls/6")
 	test("Look here http://localhost:3000/person/repo/issues/4",
-		`Look here <a href="http://localhost:3000/person/repo/issues/4">#4</a>`)
+		`Look here <a href="http://localhost:3000/person/repo/issues/4">person/repo#4</a>`)
 	test("http://localhost:3000/person/repo/issues/4#issuecomment-1234",
-		`<a href="http://localhost:3000/person/repo/issues/4#issuecomment-1234">#4</a>`)
+		`<a href="http://localhost:3000/person/repo/issues/4#issuecomment-1234">person/repo#4</a>`)
+	test("http://localhost:3000/gogits/gogs/issues/4",
+		`<a href="http://localhost:3000/gogits/gogs/issues/4">#4</a>`)
 }
 
 func TestRegExp_issueNumericPattern(t *testing.T) {
diff --git a/modules/markup/markdown/markdown_test.go b/modules/markup/markdown/markdown_test.go
index 5aa9c3d7d2..8ba51e6a1b 100644
--- a/modules/markup/markdown/markdown_test.go
+++ b/modules/markup/markdown/markdown_test.go
@@ -19,6 +19,12 @@ const AppURL = "http://localhost:3000/"
 const Repo = "gogits/gogs"
 const AppSubURL = AppURL + Repo + "/"
 
+// these values should match the Repo const above
+var localMetas = map[string]string{
+	"user": "gogits",
+	"repo": "gogs",
+}
+
 func TestRender_StandardLinks(t *testing.T) {
 	setting.AppURL = AppURL
 	setting.AppSubURL = AppSubURL
@@ -100,7 +106,8 @@ func testAnswers(baseURLContent, baseURLImages string) []string {
 <p>Ideas and codes</p>
 
 <ul>
-<li>Bezier widget (by <a href="` + AppURL + `r-lyeh" rel="nofollow">@r-lyeh</a>) <a href="http://localhost:3000/ocornut/imgui/issues/786" rel="nofollow">#786</a></li>
+<li>Bezier widget (by <a href="` + AppURL + `r-lyeh" rel="nofollow">@r-lyeh</a>) <a href="http://localhost:3000/ocornut/imgui/issues/786" rel="nofollow">ocornut/imgui#786</a></li>
+<li>Bezier widget (by <a href="` + AppURL + `r-lyeh" rel="nofollow">@r-lyeh</a>) <a href="http://localhost:3000/gogits/gogs/issues/786" rel="nofollow">#786</a></li>
 <li>Node graph editors <a href="https://github.com/ocornut/imgui/issues/306" rel="nofollow">https://github.com/ocornut/imgui/issues/306</a></li>
 <li><a href="` + baseURLContent + `/memory_editor_example" rel="nofollow">Memory Editor</a></li>
 <li><a href="` + baseURLContent + `/plot_var_example" rel="nofollow">Plot var helper</a></li>
@@ -188,6 +195,7 @@ var sameCases = []string{
 Ideas and codes
 
 - Bezier widget (by @r-lyeh) ` + AppURL + `ocornut/imgui/issues/786
+- Bezier widget (by @r-lyeh) ` + AppURL + `gogits/gogs/issues/786
 - Node graph editors https://github.com/ocornut/imgui/issues/306
 - [[Memory Editor|memory_editor_example]]
 - [[Plot var helper|plot_var_example]]`,
@@ -243,7 +251,7 @@ func TestTotal_RenderWiki(t *testing.T) {
 	answers := testAnswers(util.URLJoin(AppSubURL, "wiki/"), util.URLJoin(AppSubURL, "wiki", "raw/"))
 
 	for i := 0; i < len(sameCases); i++ {
-		line := RenderWiki([]byte(sameCases[i]), AppSubURL, nil)
+		line := RenderWiki([]byte(sameCases[i]), AppSubURL, localMetas)
 		assert.Equal(t, answers[i], line)
 	}
 
@@ -270,7 +278,7 @@ func TestTotal_RenderString(t *testing.T) {
 	answers := testAnswers(util.URLJoin(AppSubURL, "src", "master/"), util.URLJoin(AppSubURL, "raw", "master/"))
 
 	for i := 0; i < len(sameCases); i++ {
-		line := RenderString(sameCases[i], util.URLJoin(AppSubURL, "src", "master/"), nil)
+		line := RenderString(sameCases[i], util.URLJoin(AppSubURL, "src", "master/"), localMetas)
 		assert.Equal(t, answers[i], line)
 	}