Add simple substring filtering to `vcpkg list`

1 files changed, 46 insertions, 12 deletions

diff --git a/toolsrc/src/commands_list.cpp b/toolsrc/src/commands_list.cpp
index 194e4b435..87aad1991 100644
--- a/toolsrc/src/commands_list.cpp
+++ b/toolsrc/src/commands_list.cpp
@@ -4,29 +4,63 @@
 
 namespace vcpkg
 {
+    static void do_print(const StatusParagraph& pgh)
+    {
+        System::println("%-27s %-16s %s",
+                        pgh.package.displayname(),
+                        pgh.package.version,
+                        shorten_description(pgh.package.description));
+    }
+
     void list_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths)
     {
-        args.check_exact_arg_count(0);
+        static const std::string example = Strings::format(
+            "The argument should be a substring to search for, or no argument to display all installed libraries.\n%s", create_example_string("list png"));
+        args.check_max_arg_count(1, example.c_str());
 
-        std::vector<std::string> packages_output;
-        for (auto&& pgh : database_load_check(paths))
+        const StatusParagraphs status_paragraphs = database_load_check(paths);
+        std::vector<StatusParagraph> installed_packages;
+        for (auto&& pgh : status_paragraphs)
         {
             if (pgh->state == install_state_t::not_installed && pgh->want == want_t::purge)
                 continue;
-            packages_output.push_back(Strings::format("%-27s %-16s %s",
-                                                      pgh->package.displayname(),
-                                                      pgh->package.version,
-                                                      shorten_description(pgh->package.description)));
+            installed_packages.push_back(*pgh);
+        }
+
+        if (installed_packages.empty())
+        {
+            System::println("No packages are installed. Did you mean `search`?");
+            exit(EXIT_SUCCESS);
         }
-        std::sort(packages_output.begin(), packages_output.end());
-        for (auto&& package : packages_output)
+
+        std::sort(installed_packages.begin(), installed_packages.end(),
+                  [ ]( const StatusParagraph& lhs, const StatusParagraph& rhs ) -> bool
+                  {
+                      return lhs.package.displayname() < rhs.package.displayname();
+                  });
+
+        if (args.command_arguments.size() == 0)
         {
-            System::println(package.c_str());
+            for (const StatusParagraph& status_paragraph : installed_packages)
+            {
+                do_print(status_paragraph);
+            }
         }
-        if (packages_output.empty())
+        else
         {
-            System::println("No packages are installed. Did you mean `search`?");
+            // At this point there is 1 argument
+            for (const StatusParagraph& status_paragraph : installed_packages)
+            {
+                const std::string displayname = status_paragraph.package.displayname();
+                if (Strings::case_insensitive_ascii_find(displayname, args.command_arguments[0]) == displayname.end())
+                {
+                    continue;
+                }
+
+                do_print(status_paragraph);
+            }
         }
+
         exit(EXIT_SUCCESS);
     }
 }