add {COPYFILEIFNEWER} token (#2617)

Author: alchemyyy

src/base/os.lua

@@ -597,6 +597,9 @@
 			copyfile = function(v)
 				return "cp -f " .. path.normalize(v)
 			end,
+			copyfileifnewer = function(v)
+				return "cp -u " .. path.normalize(v)
+			end,
 			copydir = function(v)
 				return "cp -rf " .. path.normalize(v)
 			end,
@@ -675,6 +678,43 @@
 				-- Just use COPY instead, it actually works.
 				return "copy /B /Y " .. v
 			end,
+			copyfileifnewer = function(v)
+				-- A trailing * on the destination suppresses xcopy's
+				-- locale-dependent "File or Directory?" prompt (the old
+				-- "echo F |" hack only works on English Windows).
+				--
+				-- A trailing / on the destination marks it as a
+				-- directory; the source filename is appended so xcopy
+				-- sees a file-to-file copy.
+
+				-- Check for trailing / before normalize strips it.
+				local orig_dst = v:match('%S+%s*$') or ''
+				local orig_dst_bare = orig_dst:gsub('"', '')
+				local dst_is_dir = orig_dst_bare:sub(-1) == '/'
+
+				v = path.translate(path.normalize(v), "\\")
+
+				if dst_is_dir then
+					local src = string.match(v, '^".-"') or string.match(v, '^%S+')
+					local src_name = path.getname(src:gsub('"', ''))
+					-- Append source filename inside or outside closing quote.
+					-- Strip any trailing separator that survived translate.
+					if v:sub(-1) == '"' then
+						local base = v:sub(1, -2):gsub('[/\\]$', '')
+						v = base .. '\\' .. src_name .. '"'
+					else
+						v = v:gsub('[/\\]$', '') .. '\\' .. src_name
+					end
+				end
+
+				-- Put * inside the closing quote when the path is quoted.
+				if v:sub(-1) == '"' then
+					v = v:sub(1, -2) .. '*"'
+				else
+					v = v .. "*"
+				end
+				return "xcopy /D /Y " .. v
+			end,
 			copydir = function(v)
 				v = path.translate(path.normalize(v))
 				return "xcopy /Q /E /Y /I " .. v

tests/base/test_os.lua

@@ -360,6 +360,37 @@
 		test.isequal('IF EXIST a\\ (xcopy /Q /E /Y /I a "b" > nul) ELSE (xcopy /Q /Y /I a "b" > nul)', os.translateCommands('{COPY} a "b" ', "windows"))
 	end
 
+--
+-- os.translateCommand() COPYFILEIFNEWER tests
+--
+	function suite.translateCommand_windowsCopyFileIfNewer()
+		test.isequal('xcopy /D /Y a b*', os.translateCommands('{COPYFILEIFNEWER} a b', "windows"))
+	end
+
+	function suite.translateCommand_windowsCopyFileIfNewerWithSpaces()
+		test.isequal('xcopy /D /Y "a a" "b b*"', os.translateCommands('{COPYFILEIFNEWER} "a a" "b b"', "windows"))
+	end
+
+	function suite.translateCommand_windowsCopyFileIfNewerWithPaths()
+		test.isequal('xcopy /D /Y "src\\dir\\file.txt" "dst\\dir\\file.txt*"', os.translateCommandsAndPaths('{COPYFILEIFNEWER} %[src/dir/file.txt] %[dst/dir/file.txt]', '.', '.', "windows"))
+	end
+
+	function suite.translateCommand_windowsCopyFileIfNewerDirDst()
+		test.isequal('xcopy /D /Y "src\\Core.dll" "dst\\outdir\\Core.dll*"', os.translateCommandsAndPaths('{COPYFILEIFNEWER} %[src/Core.dll] %[dst/outdir/]', '.', '.', "windows"))
+	end
+
+	function suite.translateCommand_windowsCopyFileIfNewerDirDstQuoted()
+		test.isequal('xcopy /D /Y "src dir\\Core.dll" "dst dir\\Core.dll*"', os.translateCommandsAndPaths('{COPYFILEIFNEWER} %[src dir/Core.dll] %[dst dir/]', '.', '.', "windows"))
+	end
+
+	function suite.translateCommand_posixCopyFileIfNewer()
+		test.isequal('cp -u a b', os.translateCommands('{COPYFILEIFNEWER} a b', "posix"))
+	end
+
+	function suite.translateCommand_posixCopyFileIfNewerWithSpaces()
+		test.isequal('cp -u "a a" "b b"', os.translateCommands('{COPYFILEIFNEWER} "a a" "b b"', "posix"))
+	end
+
 --
 -- os.translateCommand() LINKDIR/LINKFILE tests
 --

website/docs/Tokens.md

@@ -103,6 +103,7 @@ The available tokens, and their replacements:
 |------------|---------------------------------------------|-----------------------|
 | {CHDIR}    | chdir {args}                                | cd {args}             |
 | {COPYFILE} | copy /B /Y {args}                           | cp -f {args}          |
+| {COPYFILEIFNEWER} | xcopy /D /Y {args}*                   | cp -u {args}          |
 | {COPYDIR}  | xcopy /Q /E /Y /I {args}                    | cp -rf {args}         |
 | {DELETE}   | del {args}                                  | rm -rf {args}         |
 | {ECHO}     | echo {args}                                 | echo {args}           |