feat(uv): add uv as a pip alternative for dealing with pypi

README.md

@@ -233,6 +233,10 @@ local DEFAULT_SETTINGS = {
         -- Whether to upgrade pip to the latest version in the virtual environment before installing packages.
         upgrade_pip = false,
 
+        ---@since 1.8.0
+        -- Whether to use uv to install packages instead of pip
+        use_uv      = false,
+
         ---@since 1.0.0
         -- These args will be added to `pip install` calls. Note that setting extra args might impact intended behavior
         -- and is not recommended.

doc/mason.txt

@@ -276,6 +276,10 @@ Example:
             -- Whether to upgrade pip to the latest version in the virtual environment before installing packages.
             upgrade_pip = false,
 
+            ---@since 2.2.1
+            -- Whether to use uv to install packages instead of pip
+            use_uv      = false,
+
             ---@since 1.0.0
             -- These args will be added to `pip install` calls. Note that setting extra args might impact intended behavior
             -- and is not recommended.

lua/mason-core/installer/compiler/compilers/pypi.lua

@@ -7,6 +7,7 @@ local M = {}
 
 ---@class PypiSource : RegistryPackageSource
 ---@field extra_packages? string[]
+---@field supported_platforms? string[]
 
 ---@param source PypiSource
 ---@param purl Purl
@@ -20,6 +21,7 @@ function M.parse(source, purl)
         pip = {
             upgrade = settings.current.pip.upgrade_pip,
             extra_args = settings.current.pip.install_args,
+            use_uv = settings.current.pip.use_uv,
         },
     }
 

lua/mason-core/installer/managers/pypi.lua

@@ -9,8 +9,11 @@ local pep440 = require "mason-core.pep440"
 local platform = require "mason-core.platform"
 local providers = require "mason-core.providers"
 local semver = require "mason-core.semver"
+local settings = require "mason.settings"
 local spawn = require "mason-core.spawn"
 
+local use_uv = settings.current.pip.use_uv
+
 local M = {}
 
 local VENV_DIR = "venv"
@@ -30,11 +33,20 @@ local function resolve_python3(candidates)
     a.scheduler()
     local available_candidates = _.filter(is_executable, candidates)
     for __, candidate in ipairs(available_candidates) do
-        ---@type string
-        local version_output = spawn[candidate]({ "--version" }):map(_.prop "stdout"):get_or_else ""
-        local ok, version = pcall(semver.new, version_output:match "Python (3%.%d+.%d+)")
-        if ok then
-            return { executable = candidate, version = version }
+        if use_uv and candidate == "uv" then
+            ---@type string
+            local version_output = spawn[candidate]({ "--version" }):map(_.prop "stdout"):get_or_else ""
+            local ok, version = pcall(semver.new, version_output:match "uv (%d+.%d+.%d+).*")
+            if ok then
+                return { executable = candidate, version = version }
+            end
+        elseif not use_uv then
+            ---@type string
+            local version_output = spawn[candidate]({ "--version" }):map(_.prop "stdout"):get_or_else ""
+            local ok, version = pcall(semver.new, version_output:match "Python (3%.%d+.%d+)")
+            if ok then
+                return { executable = candidate, version = version }
+            end
         end
     end
     return nil
@@ -66,13 +78,12 @@ local function get_versioned_candidates(supported_python_versions)
         end
         return Optional.of(executable)
     end, {
+        { semver.new "3.14.0", "python3.14" },
+        { semver.new "3.13.0", "python3.13" },
         { semver.new "3.12.0", "python3.12" },
         { semver.new "3.11.0", "python3.11" },
         { semver.new "3.10.0", "python3.10" },
-        { semver.new "3.9.0", "python3.9" },
-        { semver.new "3.8.0", "python3.8" },
-        { semver.new "3.7.0", "python3.7" },
-        { semver.new "3.6.0", "python3.6" },
+        -- the rest are EOL
     })
 end
 
@@ -85,13 +96,19 @@ local function create_venv(pkg)
 
     -- 1. Resolve stock python3 installation.
     local stock_candidates = platform.is.win and { "python", "python3" } or { "python3", "python" }
+    if use_uv then
+        table.insert(stock_candidates, 1, "uv")
+    end
     local stock_target = resolve_python3(stock_candidates)
     if stock_target then
         log.fmt_debug("Resolved stock python3 installation version %s", stock_target.version)
     end
 
     -- 2. Resolve suitable versioned python3 installation (python3.12, python3.11, etc.).
     local versioned_candidates = {}
+    if use_uv then
+        table.insert(versioned_candidates, "uv")
+    end
     if supported_python_versions ~= nil then
         if stock_target and not pep440_check_version(tostring(stock_target.version), supported_python_versions) then
             log.fmt_debug("Finding versioned candidates for %s", supported_python_versions)
@@ -111,7 +128,8 @@ local function create_venv(pkg)
     -- 3. If a versioned python3 installation was not found, warn the user if the stock python3 installation is outside
     -- the supported version range.
     if
-        target == stock_target
+        use_uv == false
+        and target == stock_target
         and supported_python_versions ~= nil
         and not pep440_check_version(tostring(target.version), supported_python_versions)
     then
@@ -133,9 +151,14 @@ local function create_venv(pkg)
         end
     end
 
-    log.fmt_debug("Found python3 installation version=%s, executable=%s", target.version, target.executable)
     ctx.stdio_sink:stdout "Creating virtual environment…\n"
-    return ctx.spawn[target.executable] { "-m", "venv", "--system-site-packages", VENV_DIR }
+    if use_uv then
+        log.fmt_debug("Found uv installation version=%s, executable=%s", target.version, target.executable)
+        return ctx.spawn[target.executable] { "venv", VENV_DIR }
+    else
+        log.fmt_debug("Found python3 installation version=%s, executable=%s", target.version, target.executable)
+        return ctx.spawn[target.executable] { "-m", "venv", "--system-site-packages", VENV_DIR }
+    end
 end
 
 ---@param ctx InstallContext
@@ -154,32 +177,58 @@ local function find_venv_executable(ctx, executable)
             return Result.success(candidate)
         end
     end
+
     return Result.failure(("Failed to find executable %q in Python virtual environment."):format(executable))
 end
 
 ---@async
 ---@param args SpawnArgs
 local function venv_python(args)
     local ctx = installer.context()
+    if use_uv then
+        return ctx.spawn["uv"](args)
+    end
     return find_venv_executable(ctx, "python"):and_then(function(python_path)
         return ctx.spawn[path.concat { ctx.cwd:get(), python_path }](args)
     end)
 end
 
+---@async
+---@param args SpawnArgs
+local function uv_python(args)
+    local ctx = installer.context()
+    local global_uv = vim.fn.exepath "uv"
+    return ctx.spawn[global_uv](args)
+end
+
 ---@async
 ---@param pkgs string[]
 ---@param extra_args? string[]
 local function pip_install(pkgs, extra_args)
-    return venv_python {
-        "-m",
-        "pip",
-        "--disable-pip-version-check",
-        "install",
-        "--no-user",
-        "--ignore-installed",
-        extra_args or vim.NIL,
-        pkgs,
-    }
+    if use_uv then
+        return uv_python {
+            "pip",
+            "install",
+            "--color",
+            "never",
+            "--directory",
+            "venv",
+            "-U",
+            extra_args or vim.NIL,
+            pkgs,
+        }
+    else
+        return venv_python {
+            "-m",
+            "pip",
+            "--disable-pip-version-check",
+            "install",
+            "--no-user",
+            "--ignore-installed",
+            extra_args or vim.NIL,
+            pkgs,
+        }
+    end
 end
 
 ---@async
@@ -193,7 +242,7 @@ function M.init(opts)
         ctx:promote_cwd()
         try(create_venv(opts.package))
 
-        if opts.upgrade_pip then
+        if opts.upgrade_pip and not use_uv then
             ctx.stdio_sink:stdout "Upgrading pip inside the virtual environment…\n"
             try(pip_install({ "pip" }, opts.install_extra_args))
         end
@@ -219,13 +268,17 @@ end
 ---@param pkg string
 function M.uninstall(pkg)
     log.fmt_debug("pypi: uninstall %s", pkg)
-    return venv_python {
-        "-m",
-        "pip",
-        "uninstall",
-        "-y",
-        pkg,
-    }
+    if use_uv then
+        return venv_python { "pip", "uninstall", "-y", pkg }
+    else
+        return venv_python {
+            "-m",
+            "pip",
+            "uninstall",
+            "-y",
+            pkg,
+        }
+    end
 end
 
 ---@param executable string

lua/mason/settings.lua

@@ -60,6 +60,10 @@ local DEFAULT_SETTINGS = {
         -- Whether to upgrade pip to the latest version in the virtual environment before installing packages.
         upgrade_pip = false,
 
+        ---@since 2.2.1
+        -- Whether to use uv to install packages instead of pip
+        use_uv = false,
+
         ---@since 1.0.0
         -- These args will be added to `pip install` calls. Note that setting extra args might impact intended behavior
         -- and is not recommended.

tests/mason-core/installer/compiler/compilers/pypi_spec.lua

@@ -31,6 +31,7 @@ describe("pypi compiler :: parsing", function()
                 pip = {
                     upgrade = true,
                     extra_args = { "--proxy", "http://localghost" },
+                    use_uv = false,
                 },
             },
             pypi.parse({ extra_packages = { "extra" } }, purl())

tests/mason-core/installer/managers/pypi_spec.lua

@@ -92,6 +92,8 @@ describe("pypi manager", function()
         stub(ctx.fs, "file_exists")
         stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.12"))
         stub(vim.fn, "executable")
+        vim.fn.executable.on_call_with("python3.14").returns(0)
+        vim.fn.executable.on_call_with("python3.13").returns(0)
         vim.fn.executable.on_call_with("python3.12").returns(1)
         stub(spawn, "python3.12")
         spawn["python3.12"].on_call_with({ "--version" }).returns(Result.success { stdout = "Python 3.12.0" })
@@ -120,13 +122,13 @@ describe("pypi manager", function()
         spy.on(ctx.stdio_sink, "stderr")
         stub(ctx, "promote_cwd")
         stub(ctx.fs, "file_exists")
-        stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.8"))
+        stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.10"))
         stub(vim.fn, "executable")
+        vim.fn.executable.on_call_with("python3.14").returns(0)
+        vim.fn.executable.on_call_with("python3.13").returns(0)
         vim.fn.executable.on_call_with("python3.12").returns(0)
         vim.fn.executable.on_call_with("python3.11").returns(0)
         vim.fn.executable.on_call_with("python3.10").returns(0)
-        vim.fn.executable.on_call_with("python3.9").returns(0)
-        vim.fn.executable.on_call_with("python3.8").returns(0)
         stub(spawn, "python3", mockx.returns(Result.success()))
         spawn.python3.on_call_with({ "--version" }).returns(Result.success { stdout = "Python 3.5.0" })
 
@@ -139,7 +141,7 @@ describe("pypi manager", function()
         end)
 
         assert.same(
-            Result.failure "Failed to find a python3 installation in PATH that meets the required versions (>=3.8). Found version: 3.5.0.",
+            Result.failure "Failed to find a python3 installation in PATH that meets the required versions (>=3.10). Found version: 3.5.0.",
             result
         )
         assert
@@ -154,13 +156,13 @@ describe("pypi manager", function()
             spy.on(ctx.stdio_sink, "stderr")
             stub(ctx, "promote_cwd")
             stub(ctx.fs, "file_exists")
-            stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.8"))
+            stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.10"))
             stub(vim.fn, "executable")
+            vim.fn.executable.on_call_with("python3.14").returns(0)
+            vim.fn.executable.on_call_with("python3.13").returns(0)
             vim.fn.executable.on_call_with("python3.12").returns(0)
             vim.fn.executable.on_call_with("python3.11").returns(0)
             vim.fn.executable.on_call_with("python3.10").returns(0)
-            vim.fn.executable.on_call_with("python3.9").returns(0)
-            vim.fn.executable.on_call_with("python3.8").returns(0)
             stub(spawn, "python3", mockx.returns(Result.success()))
             spawn.python3.on_call_with({ "--version" }).returns(Result.success { stdout = "Python 3.5.0" })
 
@@ -182,7 +184,7 @@ describe("pypi manager", function()
             }
             assert.spy(ctx.stdio_sink.stderr).was_called_with(
                 match.is_ref(ctx.stdio_sink),
-                "Warning: The resolved python3 version 3.5.0 is not compatible with the required Python versions: >=3.8.\n"
+                "Warning: The resolved python3 version 3.5.0 is not compatible with the required Python versions: >=3.10.\n"
             )
         end
     )
@@ -192,11 +194,11 @@ describe("pypi manager", function()
         spy.on(ctx.stdio_sink, "stderr")
         stub(ctx, "promote_cwd")
         stub(ctx.fs, "file_exists")
-        stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.8"))
+        stub(providers.pypi, "get_supported_python_versions", mockx.returns(Result.success ">=3.10"))
         stub(vim.fn, "executable")
-        vim.fn.executable.on_call_with("python3.12").returns(1)
+        vim.fn.executable.on_call_with("python3.14").returns(1)
         stub(spawn, "python3", mockx.returns(Result.success()))
-        spawn.python3.on_call_with({ "--version" }).returns(Result.success { stdout = "Python 3.8.0" })
+        spawn.python3.on_call_with({ "--version" }).returns(Result.success { stdout = "Python 3.10.0" })
 
         ctx:execute(function()
             pypi.init {
@@ -208,7 +210,7 @@ describe("pypi manager", function()
 
         assert.spy(ctx.promote_cwd).was_called(1)
         assert.spy(ctx.spawn.python3).was_called(1)
-        assert.spy(ctx.spawn["python3.12"]).was_called(0)
+        assert.spy(ctx.spawn["python3.14"]).was_called(0)
         assert.spy(ctx.spawn.python3).was_called_with {
             "-m",
             "venv",