From cc7c8009a1dd1720e2d7d36c2b075d1b56f11f87 Mon Sep 17 00:00:00 2001
From: Lukas Neubert <lukas.neubert3@gmail.com>
Date: Wed, 15 Jul 2020 21:55:07 +0200
Subject: [PATCH] vpm: outdated command (#5833)

---
 cmd/tools/vpm.v        | 58 ++++++++++++++++++++++++++++++++++++++++--
 cmd/v/help/default.txt |  1 +
 cmd/v/v.v              |  2 +-
 3 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/cmd/tools/vpm.v b/cmd/tools/vpm.v
index 8c4d2639f4..acec3e7c32 100644
--- a/cmd/tools/vpm.v
+++ b/cmd/tools/vpm.v
@@ -9,7 +9,7 @@ import v.vmod
 
 const (
 	default_vpm_server_urls    = ['https://vpm.best', 'https://vpm.vlang.io']
-	valid_vpm_commands         = ['help', 'search', 'install', 'update', 'remove']
+	valid_vpm_commands         = ['help', 'search', 'install', 'update', 'outdated', 'remove']
 	excluded_dirs              = ['cache', 'vlib']
 	supported_vcs_systems      = ['git', 'hg']
 	supported_vcs_folders      = ['.git', '.hg']
@@ -21,6 +21,9 @@ const (
 		'git': 'git clone --depth=1'
 		'hg': 'hg clone'
 	}
+	supported_vcs_outdate_cmds = {
+		'git': ['git rev-parse @{u}', 'git rev-parse @']
+	}
 )
 
 struct Mod {
@@ -73,6 +76,9 @@ fn main() {
 		'update' {
 			vpm_update(module_names)
 		}
+		'outdated' {
+			vpm_outdated()
+		}
 		'remove' {
 			vpm_remove(module_names)
 		}
@@ -120,7 +126,6 @@ fn vpm_search(keywords []string) {
 			break
 		}
 	}
-
 	if index == 0 {
 		println('No module(s) found for "$joined"')
 	} else {
@@ -229,6 +234,55 @@ fn vpm_update(m []string) {
 	}
 }
 
+fn vpm_outdated() {
+	module_names := get_installed_modules()
+	mut errors := 0
+	mut outdated := []string{}
+	for name in module_names {
+		final_module_path := valid_final_path_of_existing_module(name) or {
+			continue
+		}
+		os.chdir(final_module_path)
+		vcs := vcs_used_in_dir(final_module_path) or {
+			continue
+		}
+		if vcs[0] != 'git' {
+			println('Listing outdated modules is not supported with VCS {$vcs}.')
+			exit(1)
+		}
+		local_vcs_cmd := supported_vcs_outdate_cmds[vcs[0]][0]
+		local_res := os.exec(local_vcs_cmd) or {
+			errors++
+			println('Could not get local commit sha of "$name".')
+			verbose_println('Error command: $local_vcs_cmd')
+			verbose_println('Error details:\n$err')
+			continue
+		}
+		upstream_vcs_cmd := supported_vcs_outdate_cmds[vcs[0]][1]
+		upstream_res := os.exec(upstream_vcs_cmd) or {
+			errors++
+			println('Could not read upstream commit sha of "$name".')
+			verbose_println('Error command: $upstream_vcs_cmd')
+			verbose_println('Error details:\n$err')
+			continue
+		}
+		if local_res.output != upstream_res.output {
+			outdated << name
+		}
+	}
+	if outdated.len > 0 {
+		println('Outdated modules:')
+		for m in outdated {
+			println('  $m')
+		}
+	} else {
+		println('Modules are up to date.')
+	}
+	if errors > 0 {
+		exit(1)
+	}
+}
+
 fn vpm_remove(module_names []string) {
 	if settings.is_help {
 		vhelp.show_topic('remove')
diff --git a/cmd/v/help/default.txt b/cmd/v/help/default.txt
index 02b73e891b..d8ea51512b 100644
--- a/cmd/v/help/default.txt
+++ b/cmd/v/help/default.txt
@@ -31,6 +31,7 @@ V supports the following commands:
    remove            Remove a module that was installed from VPM.
    search            Search for a module from VPM.
    update            Update an installed module from VPM.
+   outdated          List installed modules that need updates.
 * Others:
    build             Build a V code in the provided path (the default, so you can skip the word `build`).
    translate         Translate C code to V (coming soon in 0.3).
diff --git a/cmd/v/v.v b/cmd/v/v.v
index 6565d80a6d..13122a2064 100644
--- a/cmd/v/v.v
+++ b/cmd/v/v.v
@@ -70,7 +70,7 @@ fn main() {
 			println('Translating C to V will be available in V 0.3')
 			return
 		}
-		'search', 'install', 'update', 'remove' {
+		'search', 'install', 'update', 'outdated', 'remove' {
 			util.launch_tool(prefs.is_verbose, 'vpm', os.args[1..])
 			return
 		}