cpython: 2eb99070a38f (original) (raw)

Mercurial > cpython

changeset 94764:2eb99070a38f

Issue #23465: Implement PEP 486 - Make the Python Launcher aware of virtual environments (patch by Paul Moore) [#23465]

line wrap: on

line diff

--- a/Doc/using/windows.rst +++ b/Doc/using/windows.rst @@ -404,6 +404,16 @@ If you see the following error, you do n Per-user installations of Python do not add the launcher to :envvar:PATH unless the option was selected on installation. +Virtual environments +^^^^^^^^^^^^^^^^^^^^ + +If the launcher is run with no explicit Python version specification, and a +virtual environment (created with the standard library :mod:venv module or +the external virtualenv tool) active, the launcher will run the virtual +environment's interpreter rather than the global one. To run the global +interpreter, either deactivate the virtual environment, or explicitly specify +the global Python version. + From a script ^^^^^^^^^^^^^ @@ -478,6 +488,16 @@ be used by the launcher without modifica on Windows which you hope will be useful on Unix, you should use one of the shebang lines starting with /usr. +Any of the above virtual commands can be suffixed with an explicit version +(either just the major version, or the major and minor version) - for example +/usr/bin/python2.7 - which will cause that specific version to be located +and used. + +The /usr/bin/env form of shebang line has one further special property. +Before looking for installed Python interpreters, this form will search the +executable :envvar:PATH for a Python executable. This corresponds to the +behaviour of the Unix env program, which performs a :envvar:PATH search. + Arguments in shebang lines --------------------------

--- a/Doc/whatsnew/3.5.rst +++ b/Doc/whatsnew/3.5.rst @@ -123,6 +123,18 @@ manually, and should make it more robust :pep:475 -- Retry system calls failing with EINTR +PEP 486: Make the Python Launcher aware of virtual environments +--------------------------------------------------------------- + +:pep:486 makes the Windows launcher (see :pep:397) aware of an active +virtual environment. When the default interpreter would be used and the +VIRTUAL_ENV environment variable is set, the interpreter in the virtual +environment will be used. + +.. seealso:: +

• :pep:486 -- Make the Python Launcher aware of virtual environments

+ Other Language Changes ======================

--- a/Misc/NEWS +++ b/Misc/NEWS @@ -77,6 +77,9 @@ Build Windows ------- +- Issue #23465: Implement PEP 486 - Make the Python Launcher aware of virtual

• environments. Patch by Paul Moore. +

• Issue #23437: Make user scripts directory versioned on Windows. Patch by Paul Moore.

--- a/PC/launcher.c +++ b/PC/launcher.c @@ -384,6 +384,31 @@ find_python_by_version(wchar_t const * w } +static wchar_t * +find_python_by_venv() +{

• static wchar_t venv_python[MAX_PATH];
• wchar_t *virtual_env = get_env(L"VIRTUAL_ENV");
• DWORD attrs;

+

• /* Check for VIRTUAL_ENV environment variable */
• if (virtual_env == NULL || virtual_env[0] == L'\0') {

•    return NULL;[](#l4.16)

• }

+

• /* Check for a python executable in the venv */
• debug(L"Checking for Python executable in virtual env '%ls'\n", virtual_env);
• _snwprintf_s(venv_python, MAX_PATH, _TRUNCATE,

•        L"%ls\\Scripts\\%ls", virtual_env, PYTHON_EXECUTABLE);[](#l4.22)

• attrs = GetFileAttributesW(venv_python);
• if (attrs == INVALID_FILE_ATTRIBUTES) {

•    debug(L"Python executable %ls missing from virtual env\n", venv_python);[](#l4.25)

•    return NULL;[](#l4.26)

• }

+

• return venv_python;

+} + static wchar_t appdata_ini_path[MAX_PATH]; static wchar_t launcher_ini_path[MAX_PATH]; @@ -1309,6 +1334,7 @@ process(int argc, wchar_t ** argv) { wchar_t * wp; wchar_t * command;

• wchar_t * executable; wchar_t * p; int rc = 0; size_t plen; @@ -1453,6 +1479,7 @@ process(int argc, wchar_t ** argv) if (ip == NULL) error(RC_NO_PYTHON, L"Requested Python version (%ls) not [](#l4.45)

installed", &p[1]);

•        executable = ip->executable;[](#l4.47)
         command += wcslen(p);[](#l4.48)
         command = skip_whitespace(command);[](#l4.49)
     }[](#l4.50)

@@ -1470,9 +1497,16 @@ installed", &p[1]); #endif if (!valid) {

•    ip = locate_python(L"");[](#l4.55)

•    if (ip == NULL)[](#l4.56)

•        error(RC_NO_PYTHON, L"Can't find a default Python.");[](#l4.57)

•    /* Look for an active virtualenv */[](#l4.58)

•    executable = find_python_by_venv();[](#l4.59)

+

•    /* If we didn't find one, look for the default Python */[](#l4.61)

•    if (executable == NULL) {[](#l4.62)

•        ip = locate_python(L"");[](#l4.63)

•        if (ip == NULL)[](#l4.64)

•            error(RC_NO_PYTHON, L"Can't find a default Python.");[](#l4.65)

•        executable = ip->executable;[](#l4.66)

•    }[](#l4.67)
     if ((argc == 2) && (!_wcsicmp(p, L"-h") || !_wcsicmp(p, L"--help"))) {[](#l4.68)

#if defined(_M_X64) BOOL canDo64bit = TRUE; @@ -1500,7 +1534,7 @@ Launcher arguments:\n\n[](#l4.71) fflush(stdout); } }

• invoke_child(ip->executable, NULL, command);

• invoke_child(executable, NULL, command); return rc; }