t0111: Add basic tests for Lua filters

* Validate the email filter by manipulating stdin. Additional checks for
  all the arguments can be added in a later patch.

* Add the exec prefix to all informational messages.

* Rename the filter repository to filter-exec. The Git repository itself
  is not renamed since it can be shared amongst all filter types.

* In the filter checks, check whether all arguments are passed properly
  instead of validating the buffer/stdin only.

Signed-off-by: Lukas Fleischer <cgit@cryptocrack.de>

tests/filters/capitalize-argv1.sh

@@ -1,3 +0,0 @@
-#!/bin/sh
-
-echo "$1" | tr '[:lower:]' '[:upper:]'

tests/filters/capitalize-buffer.lua

@@ -0,0 +1,17 @@
+function filter_open(...)
+	buffer = ""
+	for i = 1, select("#", ...) do
+		buffer = buffer .. select(i, ...) .. " "
+	end
+end
+
+function filter_close()
+	html(buffer)
+	return 0
+end
+
+function filter_write(str)
+	buffer = buffer .. string.upper(str)
+end
+
+

tests/filters/capitalize-stdin.sh

@@ -1,3 +1,4 @@
 #!/bin/sh
 
+[ "$#" -gt 0 ] && printf "%s " "$*"
 tr '[:lower:]' '[:upper:]'