Lead a readme's relative links into the tree

A browser resolved them against the about page, where nothing lives
now that the page answers 404 below itself. They resolve the way
GitHub resolves a readme's links instead, from the readme's directory
and on the branch it was read from.

2 files changed, 44 insertions, 3 deletions

diff --git a/tests/extensions/harness.lua b/tests/extensions/harness.luaindex d9318ee..fc83a73 100644--- a/tests/extensions/harness.lua+++ b/tests/extensions/harness.lua@@ -46,16 +46,23 @@ html_attr = sink(function(s) 	return (s:gsub("[&<>'\"]", attr_map)) end) +-- The bytes url_escape_table encodes, which are those a url path cannot+-- carry plainly and those an attribute or a query would misread.+html_url_path = sink(function(s)+	return (s:gsub("[%c \"#%%&'+<=>?\\^`{|}\128-\255]", function(c)+		return string.format("%%%02X", c:byte())+	end))+end)+ -- No shipped extension calls the remaining sinks, so rather than risk an -- unfaithful copy quietly passing a test, using one fails loudly until its--- escaping is mirrored from source/html.c the way the three above are.+-- escaping is mirrored from source/html.c the way the ones above are. local function unmirrored(name) 	return function() 		error(name .. " is not mirrored by the test harness yet") 	end end -html_url_path = unmirrored("html_url_path") html_url_arg = unmirrored("html_url_arg") html_include = unmirrored("html_include") 
diff --git a/tests/extensions/harness.lua b/tests/extensions/harness.lua
index d9318ee..fc83a73 100644
--- a/tests/extensions/harness.lua
+++ b/tests/extensions/harness.lua
@@ -46,16 +46,23 @@ html_attr = sink(function(s)
 	return (s:gsub("[&<>'\"]", attr_map))
 end)
 
+-- The bytes url_escape_table encodes, which are those a url path cannot
+-- carry plainly and those an attribute or a query would misread.
+html_url_path = sink(function(s)
+	return (s:gsub("[%c \"#%%&'+<=>?\\^`{|}\128-\255]", function(c)
+		return string.format("%%%02X", c:byte())
+	end))
+end)
+
 -- No shipped extension calls the remaining sinks, so rather than risk an
 -- unfaithful copy quietly passing a test, using one fails loudly until its
--- escaping is mirrored from source/html.c the way the three above are.
+-- escaping is mirrored from source/html.c the way the ones above are.
 local function unmirrored(name)
 	return function()
 		error(name .. " is not mirrored by the test harness yet")
 	end
 end
 
-html_url_path = unmirrored("html_url_path")
 html_url_arg = unmirrored("html_url_arg")
 html_include = unmirrored("html_include")
 
diff --git a/tests/extensions/test-about-render.lua b/tests/extensions/test-about-render.luaindex b0379b7..4f8b532 100644--- a/tests/extensions/test-about-render.lua+++ b/tests/extensions/test-about-render.lua@@ -28,6 +28,11 @@ local function render(filename, text) 	return h.run({ filename }, { text }) end +-- A readme tracked in a repository comes with the url of its tree.+local function render_tree(filename, query, text)+	return h.run({ filename, "/r/tree/", query }, { text })+end+ -- Dispatch and the plain text rendering need nothing but the script itself, -- so they run whatever became of lpeg. @@ -107,7 +112,36 @@ out = render("README.md", "[docs](https://example.com/docs)") h.contains("an https link renders as an anchor", out, "<a href='https://example.com/docs'>docs</a>")  out = render("README.md", "[docs](docs/page.html)")-h.contains("a relative link renders as an anchor", out, "<a href='docs/page.html'>docs</a>")+h.contains("with no tree a relative link stays as written", out, "<a href='docs/page.html'>docs</a>")++out = render_tree("README.md", "", "[road](ROADMAP.md)")+h.contains("a relative link leads into the tree", out, "<a href='/r/tree/ROADMAP.md'>road</a>")++out = render_tree("docs/README.md", "", "[a](guide.md#setup) [b](../NEWS) [c](/src/x.c)")+h.contains("a link resolves against the readme's directory", out, "href='/r/tree/docs/guide.md#setup'")+h.contains("dot segments fold", out, "href='/r/tree/NEWS'")+h.contains("a leading slash names the root", out, "href='/r/tree/src/x.c'")++out = render_tree("docs/README.md", "", "[up](../../../etc/passwd)")+h.contains("no link climbs above the root", out, "href='/r/tree/etc/passwd'")++out = render_tree("README.md", "?h=next", "[a](NEWS#top)")+h.contains("the ref's query comes before the fragment", out, "href='/r/tree/NEWS?h=next#top'")++out = render_tree("README.md", "&h=next", "[a](NEWS)")+h.contains("the query is escaped for the attribute", out, "href='/r/tree/NEWS&amp;h=next'")++out = render_tree("README.md", "", "[a](my%20file.md) [b](a&b.md) [c](f.md?plain=1)")+h.contains("an encoded path is encoded only once", out, "href='/r/tree/my%20file.md'")+h.contains("a path is escaped for the url", out, "href='/r/tree/a%26b.md'")+h.contains("a query in a link is dropped", out, "href='/r/tree/f.md'")++out = render_tree("README.md", "", "[a](x%00y)")+h.contains("an encoded nul stays encoded", out, "href='/r/tree/x%2500y'")++out = render_tree("README.md", "", "[a](#usage) [b](https://example.com/x)")+h.contains("a fragment stays on the page", out, "href='#usage'")+h.contains("an absolute link is left alone", out, "href='https://example.com/x'")  out = render("README.md", "[mail](mailto:a@example.com)") h.contains("a mailto link renders as an anchor", out, "<a href='mailto:a@example.com'>mail</a>")
diff --git a/tests/extensions/test-about-render.lua b/tests/extensions/test-about-render.lua
index b0379b7..4f8b532 100644
--- a/tests/extensions/test-about-render.lua
+++ b/tests/extensions/test-about-render.lua
@@ -28,6 +28,11 @@ local function render(filename, text)
 	return h.run({ filename }, { text })
 end
 
+-- A readme tracked in a repository comes with the url of its tree.
+local function render_tree(filename, query, text)
+	return h.run({ filename, "/r/tree/", query }, { text })
+end
+
 -- Dispatch and the plain text rendering need nothing but the script itself,
 -- so they run whatever became of lpeg.
 
@@ -107,7 +112,36 @@ out = render("README.md", "[docs](https://example.com/docs)")
 h.contains("an https link renders as an anchor", out, "<a href='https://example.com/docs'>docs</a>")
 
 out = render("README.md", "[docs](docs/page.html)")
-h.contains("a relative link renders as an anchor", out, "<a href='docs/page.html'>docs</a>")
+h.contains("with no tree a relative link stays as written", out, "<a href='docs/page.html'>docs</a>")
+
+out = render_tree("README.md", "", "[road](ROADMAP.md)")
+h.contains("a relative link leads into the tree", out, "<a href='/r/tree/ROADMAP.md'>road</a>")
+
+out = render_tree("docs/README.md", "", "[a](guide.md#setup) [b](../NEWS) [c](/src/x.c)")
+h.contains("a link resolves against the readme's directory", out, "href='/r/tree/docs/guide.md#setup'")
+h.contains("dot segments fold", out, "href='/r/tree/NEWS'")
+h.contains("a leading slash names the root", out, "href='/r/tree/src/x.c'")
+
+out = render_tree("docs/README.md", "", "[up](../../../etc/passwd)")
+h.contains("no link climbs above the root", out, "href='/r/tree/etc/passwd'")
+
+out = render_tree("README.md", "?h=next", "[a](NEWS#top)")
+h.contains("the ref's query comes before the fragment", out, "href='/r/tree/NEWS?h=next#top'")
+
+out = render_tree("README.md", "&h=next", "[a](NEWS)")
+h.contains("the query is escaped for the attribute", out, "href='/r/tree/NEWS&amp;h=next'")
+
+out = render_tree("README.md", "", "[a](my%20file.md) [b](a&b.md) [c](f.md?plain=1)")
+h.contains("an encoded path is encoded only once", out, "href='/r/tree/my%20file.md'")
+h.contains("a path is escaped for the url", out, "href='/r/tree/a%26b.md'")
+h.contains("a query in a link is dropped", out, "href='/r/tree/f.md'")
+
+out = render_tree("README.md", "", "[a](x%00y)")
+h.contains("an encoded nul stays encoded", out, "href='/r/tree/x%2500y'")
+
+out = render_tree("README.md", "", "[a](#usage) [b](https://example.com/x)")
+h.contains("a fragment stays on the page", out, "href='#usage'")
+h.contains("an absolute link is left alone", out, "href='https://example.com/x'")
 
 out = render("README.md", "[mail](mailto:a@example.com)")
 h.contains("a mailto link renders as an anchor", out, "<a href='mailto:a@example.com'>mail</a>")