Compare branches, commits and tags with each other (#6991)

* Supports tags when comparing commits or branches

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Hide headline when only comparing and don't load unused data

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Merges compare logics to allow comparing branches, commits and tags with eachother

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Display branch or tag instead of commit when used for comparing

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Show pull request form after click on button

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Transfers relevant pull.go changes from master to compare.go

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Fixes error when comparing forks against a commit or tag

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Removes console.log from JavaScript file

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Show icon next to commit reference when comparing branch or tag

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Updates css file

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Fixes import order

* Renames template variable

* Update routers/repo/compare.go

Co-Authored-By: zeripath <art27@cantab.net>

* Update from master

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Allow short-shas in compare

* Renames prInfo to compareInfo

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Check PR permissions only if compare is pull request

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Adjusts comment

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Use compareInfo instead of prInfo

2 files changed, 74 insertions, 94 deletions

diff --git a/templates/repo/diff/compare.tmpl b/templates/repo/diff/compare.tmpl
new file mode 100644
index 0000000000..cc727422d7
--- /dev/null
+++ b/templates/repo/diff/compare.tmpl
@@ -0,0 +1,74 @@
+{{template "base/head" .}}
+<div class="repository diff {{if .PageIsComparePull}}compare pull{{end}}">
+	{{template "repo/header" .}}
+	<div class="ui container {{if .IsSplitStyle}}fluid padded{{end}}">
+
+	{{if .PageIsComparePull}}
+		<h2 class="ui header">
+			{{.i18n.Tr "repo.pulls.compare_changes"}}
+			<div class="sub header">{{.i18n.Tr "repo.pulls.compare_changes_desc"}}</div>
+		</h2>
+		<div class="ui segment choose branch">
+			<span class="octicon octicon-git-compare"></span>
+			<div class="ui floating filter dropdown" data-no-results="{{.i18n.Tr "repo.pulls.no_results"}}">
+				<div class="ui basic small button">
+					<span class="text">{{.i18n.Tr "repo.pulls.compare_base"}}: {{$.BaseName}}:{{$.BaseBranch}}</span>
+					<i class="dropdown icon"></i>
+				</div>
+				<div class="menu">
+					<div class="ui icon search input">
+						<i class="filter icon"></i>
+						<input name="search" placeholder="{{.i18n.Tr "repo.pulls.filter_branch"}}...">
+					</div>
+					<div class="scrolling menu">
+						{{range .Branches}}
+							<div class="item {{if eq $.BaseBranch .}}selected{{end}}" data-url="{{$.RepoLink}}/compare/{{EscapePound .}}...{{if not $.PullRequestCtx.SameRepo}}{{$.HeadUser.Name}}:{{end}}{{EscapePound $.HeadBranch}}">{{$.BaseName}}:{{.}}</div>
+						{{end}}
+					</div>
+				</div>
+			</div>
+			...
+			<div class="ui floating filter dropdown">
+				<div class="ui basic small button">
+					<span class="text">{{.i18n.Tr "repo.pulls.compare_compare"}}: {{$.HeadUser.Name}}:{{$.HeadBranch}}</span>
+					<i class="dropdown icon"></i>
+				</div>
+				<div class="menu">
+					<div class="ui icon search input">
+						<i class="filter icon"></i>
+						<input name="search" placeholder="{{.i18n.Tr "repo.pulls.filter_branch"}}...">
+					</div>
+					<div class="scrolling menu">
+						{{range .HeadBranches}}
+							<div class="{{if eq $.HeadBranch .}}selected{{end}} item" data-url="{{$.RepoLink}}/compare/{{EscapePound $.BaseBranch}}...{{if not $.PullRequestCtx.SameRepo}}{{$.HeadUser.Name}}:{{end}}{{EscapePound .}}">{{$.HeadUser.Name}}:{{.}}</div>
+						{{end}}
+					</div>
+				</div>
+			</div>
+		</div>
+	{{end}}
+
+	{{if .IsNothingToCompare}}
+    	<div class="ui segment">{{.i18n.Tr "repo.pulls.nothing_to_compare"}}</div>
+    {{else if .PageIsComparePull}}
+		{{if .HasPullRequest}}
+        	<div class="ui segment">
+        		{{.i18n.Tr "repo.pulls.has_pull_request" $.RepoLink $.RepoRelPath .PullRequest.Index | Safe}}
+        	</div>
+        {{else}}
+        	<div class="ui info message show-form-container">
+        		<button class="ui button green show-form">{{.i18n.Tr "repo.pulls.new"}}</button>
+        	</div>
+        	<div class="pullrequest-form" style="display: none">
+        		{{template "repo/issue/new_form" .}}
+        	</div>
+        	{{template "repo/commits_table" .}}
+        	{{template "repo/diff/box" .}}
+        {{end}}
+	{{else}}
+		{{template "repo/commits_table" .}}
+		{{template "repo/diff/box" .}}
+	{{end}}
+	</div>
+</div>
+{{template "base/footer" .}}
diff --git a/templates/repo/diff/page.tmpl b/templates/repo/diff/page.tmpl
deleted file mode 100644
index c35e2a415b..0000000000
--- a/templates/repo/diff/page.tmpl
+++ /dev/null
@@ -1,94 +0,0 @@
-{{template "base/head" .}}
-<div class="repository diff">
-	{{template "repo/header" .}}
-	<div class="ui container {{if .IsSplitStyle}}fluid padded{{end}}">
-		{{if .IsDiffCompare }}
-			{{template "repo/commits_table" .}}
-		{{else}}
-			<div class="ui top attached info clearing segment {{if .Commit.Signature}} isSigned {{if .Verification.Verified }} isVerified {{end}}{{end}}">
-				<a class="ui floated right blue tiny button" href="{{EscapePound .SourcePath}}">
-					{{.i18n.Tr "repo.diff.browse_source"}}
-				</a>
-				<h3 class="has-emoji">{{RenderCommitMessage .Commit.Message $.RepoLink $.Repository.ComposeMetas}}{{template "repo/commit_status" .CommitStatus}}</h3>
-				{{if IsMultilineCommitMessage .Commit.Message}}
-					<pre class="commit-body">{{RenderCommitBody .Commit.Message $.RepoLink $.Repository.ComposeMetas}}</pre>
-				{{end}}
-				<span class="text grey"><i class="octicon octicon-git-branch"></i>{{.BranchName}}</span>
-			</div>
-			<div class="ui attached info segment {{if .Commit.Signature}} isSigned {{if .Verification.Verified }} isVerified {{end}}{{end}}">
-				<div class="ui stackable grid">
-					<div class="nine wide column">
-						{{if .Author}}
-							<img class="ui avatar image" src="{{.Author.RelAvatarLink}}" />
-						{{if .Author.FullName}}
-						<a href="{{.Author.HomeLink}}"><strong>{{.Author.FullName}}</strong></a> {{if .IsSigned}}<{{.Commit.Author.Email}}>{{end}}
-						{{else}}
-						<a href="{{.Author.HomeLink}}"><strong>{{.Commit.Author.Name}}</strong></a> {{if .IsSigned}}<{{.Commit.Author.Email}}>{{end}}
-						{{end}}
-						{{else}}
-							<img class="ui avatar image" src="{{AvatarLink .Commit.Author.Email}}" />
-							<strong>{{.Commit.Author.Name}}</strong>
-						{{end}}
-						<span class="text grey" id="authored-time">{{TimeSince .Commit.Author.When $.Lang}}</span>
-					</div>
-					<div class="seven wide right aligned column">
-						<div class="ui horizontal list">
-							{{if .Parents}}
-								<div class="item">
-									{{.i18n.Tr "repo.diff.parent"}}
-								</div>
-								<div class="item">
-									{{range .Parents}}
-										<a class="ui blue sha label" href="{{$.RepoLink}}/commit/{{.}}">{{ShortSha .}}</a>
-									{{end}}
-								</div>
-							{{end}}
-							<div class="mobile-only"></div>
-							<div class="item">{{.i18n.Tr "repo.diff.commit"}}</div>
-							<div class="item"><span class="ui blue sha label">{{ShortSha .CommitID}}</span></div>
-						</div>
-					</div><!-- end column -->
-				</div><!-- end grid -->
-			</div>
-			{{if .Commit.Signature}}
-				{{if .Verification.Verified }}
-					<div class="ui bottom attached positive message">
-					  <i class="green lock icon"></i>
-						<span>{{.i18n.Tr "repo.commits.signed_by"}}:</span>
-						<a href="{{.Verification.SigningUser.HomeLink}}"><strong>{{.Commit.Committer.Name}}</strong></a> <{{.Commit.Committer.Email}}>
-						<span class="pull-right"><span>{{.i18n.Tr "repo.commits.gpg_key_id"}}:</span> {{.Verification.SigningKey.KeyID}}</span>
-					</div>
-				{{else}}
-					<div class="ui bottom attached message">
-					  <i class="grey unlock icon"></i>
-					  {{.i18n.Tr .Verification.Reason}}
-					</div>
-				{{end}}
-			{{end}}
-			{{if .Note}}
-				<div class="ui top attached info segment message git-notes">
-					<i class="sticky note icon"></i>
-					{{.i18n.Tr "repo.diff.git-notes"}}:
-					{{if .NoteAuthor}}
-						<a href="{{.NoteAuthor.HomeLink}}">
-							{{if .NoteAuthor.FullName}}
-							  <strong>{{.NoteAuthor.FullName}}</strong>
-							{{else}}
-							  <strong>{{.NoteCommit.Author.Name}}</strong>
-							{{end}}
-						</a>
-					{{else}}
-						<strong>{{.NoteCommit.Author.Name}}</strong>
-					{{end}}
-					<span class="text grey" id="note-authored-time">{{TimeSince .NoteCommit.Author.When $.Lang}}</span>
-				</div>
-				<div class="ui bottom attached info segment git-notes">
-					<pre class="commit-body">{{RenderNote .Note $.RepoLink $.Repository.ComposeMetas}}</pre>
-				</div>
-			{{end}}
-		{{end}}
-
-		{{template "repo/diff/box" .}}
-	</div>
-</div>
-{{template "base/footer" .}}