# Copyright 2005 Dave Abrahams
# Copyright 2002, 2003, 2004, 2005, 2006 Vladimir Prus
# Copyright 2014-2015 Rene Rivera
# Copyright 2014 Microsoft Corporation
# Distributed under the Boost Software License, Version 1.0.
# (See accompanying file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)

# This module implements regression testing framework. It declares a number of
# main target rules which perform some action and, if the results are OK,
# creates an output file.
#
# The exact list of rules is:
# 'compile'       -- creates .test file if compilation of sources was
#                    successful.
# 'compile-fail'  -- creates .test file if compilation of sources failed.
# 'run'           -- creates .test file is running of executable produced from
#                    sources was successful. Also leaves behind .output file
#                    with the output from program run.
# 'run-fail'      -- same as above, but .test file is created if running fails.
#
# In all cases, presence of .test file is an indication that the test passed.
# For more convenient reporting, you might want to use C++ Boost regression
# testing utilities (see http://www.boost.org/more/regression.html).
#
# For historical reason, a 'unit-test' rule is available which has the same
# syntax as 'exe' and behaves just like 'run'.

# Things to do:
#  - Teach compiler_status handle Jamfile.v2.
# Notes:
#  - <no-warn> is not implemented, since it is Como-specific, and it is not
#    clear how to implement it
#  - std::locale-support is not implemented (it is used in one test).


import alias ;
import "class" ;
import common ;
import errors ;
import feature ;
import generators ;
import os ;
import path ;
import project ;
import property ;
import property-set ;
import regex ;
import sequence ;
import targets ;
import toolset ;
import type ;
import virtual-target ;


rule init ( )
{
}


# Feature controlling the command used to launch test programs.
feature.feature testing.launcher   : : free optional ;

feature.feature test-info          : : free incidental ;
feature.feature testing.arg        : : free incidental ;
feature.feature testing.input-file : : free dependency ;

feature.feature preserve-test-targets : on off : incidental propagated ;

# Feature to control whether executable binaries are run as part of test.
# This can be used to just compile test cases in cross compilation situations.
feature.feature testing.execute : on off : incidental propagated ;
feature.set-default testing.execute : on ;

# Register target types.
type.register TEST         : test          ;
type.register COMPILE      :        : TEST ;
type.register COMPILE_FAIL :        : TEST ;
type.register RUN_OUTPUT   : run           ;
type.register RUN          :        : TEST ;
type.register RUN_FAIL     :        : TEST ;
type.register LINK_FAIL    :        : TEST ;
type.register LINK         :        : TEST ;
type.register UNIT_TEST    : passed : TEST ;


# Suffix to denote test target directory
#
.TEST-DIR-SUFFIX = ".test" ;
if [ os.name ] = VMS
{
    .TEST-DIR-SUFFIX = "$test" ;
}

# Declare the rules which create main targets. While the 'type' module already
# creates rules with the same names for us, we need extra convenience: default
# name of main target, so write our own versions.

# Helper rule. Create a test target, using basename of first source if no target
# name is explicitly passed. Remembers the created target in a global variable.
#
rule make-test ( target-type : sources + : requirements * : target-name ? )
{
    target-name ?= $(sources[1]:D=:S=) ;

    # Having periods (".") in the target name is problematic because the typed
    # generator will strip the suffix and use the bare name for the file
    # targets. Even though the location-prefix averts problems most times it
    # does not prevent ambiguity issues when referring to the test targets. For
    # example when using the XML log output. So we rename the target to remove
    # the periods, and provide an alias for users.
    local real-name = [ regex.replace $(target-name) "[.]" "~" ] ;

    local project = [ project.current ] ;
    # The <location-prefix> forces the build system for generate paths in the
    # form '$build_dir/array1$(.TEST-DIR-SUFFIX)/gcc/debug'. This is necessary
    # to allow post-processing tools to work.
    local t = [ targets.create-typed-target [ type.type-from-rule-name
        $(target-type) ] : $(project) : $(real-name) : $(sources) :
        $(requirements) <location-prefix>$(real-name)$(.TEST-DIR-SUFFIX) ] ;

    # The alias to the real target, per period replacement above.
    if $(real-name) != $(target-name)
    {
        alias $(target-name) : $(t) ;
    }

    # Remember the test (for --dump-tests). A good way would be to collect all
    # given a project. This has some technical problems: e.g. we can not call
    # this dump from a Jamfile since projects referred by 'build-project' are
    # not available until the whole Jamfile has been loaded.
    .all-tests += $(t) ;
    return $(t) ;
}


# Note: passing more that one cpp file here is known to fail. Passing a cpp file
# and a library target works.
#
rule compile ( sources + : requirements * : target-name ? )
{
    return [ make-test compile : $(sources) : $(requirements) : $(target-name) ]
        ;
}


rule compile-fail ( sources + : requirements * : target-name ? )
{
    return [ make-test compile-fail : $(sources) : $(requirements) :
        $(target-name) ] ;
}


rule link ( sources + : requirements * : target-name ? )
{
    return [ make-test link : $(sources) : $(requirements) : $(target-name) ] ;
}


rule link-fail ( sources + : requirements * : target-name ? )
{
    return [ make-test link-fail : $(sources) : $(requirements) : $(target-name)
        ] ;
}


rule handle-input-files ( input-files * )
{
    if $(input-files[2])
    {
        # Check that sorting made when creating property-set instance will not
        # change the ordering.
        if [ sequence.insertion-sort $(input-files) ] != $(input-files)
        {
            errors.user-error "Names of input files must be sorted alphabetically"
                : "due to internal limitations" ;
        }
    }
    return <testing.input-file>$(input-files) ;
}


rule run ( sources + : args * : input-files * : requirements * : target-name ? :
    default-build * )
{
    requirements += <testing.arg>$(args:J=" ") ;
    requirements += [ handle-input-files $(input-files) ] ;
    return [ make-test run : $(sources) : $(requirements) : $(target-name) ] ;
}


rule run-fail ( sources + : args * : input-files * : requirements * :
    target-name ? : default-build * )
{
    requirements += <testing.arg>$(args:J=" ") ;
    requirements += [ handle-input-files $(input-files) ] ;
    return [ make-test run-fail : $(sources) : $(requirements) : $(target-name)
        ] ;
}


# Use 'test-suite' as a synonym for 'alias', for backward compatibility.
IMPORT : alias : : test-suite ;


# For all main targets in 'project-module', which are typed targets with type
# derived from 'TEST', produce some interesting information.
#
rule dump-tests
{
    for local t in $(.all-tests)
    {
        dump-test $(t) ;
    }
}


# Given a project location in normalized form (slashes are forward), compute the
# name of the Boost library.
#
local rule get-library-name ( path )
{
    # Path is in normalized form, so all slashes are forward.
    local match1 = [ MATCH /(tools|libs)/(.*)/(test|example) : $(path) ] ;
    local match2 = [ MATCH /(tools|libs)/(.*)$ : $(path) ] ;
    local match3 = [ MATCH (/status$) : $(path) ] ;

    if $(match1) { return $(match1[2]) ; }
    else if $(match2) { return $(match2[2]) ; }
    else if $(match3) { return "" ; }
    else if --dump-tests in [ modules.peek : ARGV ]
    {
        # The 'run' rule and others might be used outside boost. In that case,
        # just return the path, since the 'library name' makes no sense.
        return $(path) ;
    }
}


# Was an XML dump requested?
.out-xml = [ MATCH --out-xml=(.*) : [ modules.peek : ARGV ] ] ;


# Takes a target (instance of 'basic-target') and prints
#   - its type
#   - its name
#   - comments specified via the <test-info> property
#   - relative location of all source from the project root.
#
rule dump-test ( target )
{
    local type = [ $(target).type ] ;
    local name = [ $(target).name ] ;
    local project = [ $(target).project ] ;

    local project-root = [ $(project).get project-root ] ;
    local library = [ get-library-name [ path.root [ $(project).get location ]
        [ path.pwd ] ] ] ;
    if $(library)
    {
        name = $(library)/$(name) ;
    }

    local sources = [ $(target).sources ] ;
    local source-files ;
    for local s in $(sources)
    {
        if [ class.is-a $(s) : file-reference ]
        {
            local location = [ path.root [ path.root [ $(s).name ]
                [ $(s).location ] ] [ path.pwd ] ] ;

            source-files += [ path.relative-to [ path.root $(project-root)
                [ path.pwd ] ] $(location) ] ;
        }
    }

    local target-name =
        [ $(project).get location ] // [ $(target).name ] $(.TEST-DIR-SUFFIX) ;
    target-name = $(target-name:J=) ;

    local r = [ $(target).requirements ] ;
    # Extract values of the <test-info> feature.
    local test-info = [ $(r).get <test-info> ] ;

    # If the user requested XML output on the command-line, add the test info to
    # that XML file rather than dumping them to stdout.
    if $(.out-xml)
    {
        local nl = "
" ;
        .contents on $(.out-xml) +=
            "$(nl)  <test type=\"$(type)\" name=\"$(name)\">"
            "$(nl)    <target><![CDATA[$(target-name)]]></target>"
            "$(nl)    <info><![CDATA[$(test-info)]]></info>"
            "$(nl)    <source><![CDATA[$(source-files)]]></source>"
            "$(nl)  </test>"
            ;
    }
    else
    {
        # Format them into a single string of quoted strings.
        test-info = \"$(test-info:J=\"\ \")\" ;

        ECHO boost-test($(type)) \"$(name)\" [$(test-info)] ":"
            \"$(source-files)\" ;
    }
}


# Register generators. Depending on target type, either 'expect-success' or
# 'expect-failure' rule will be used.
generators.register-standard testing.expect-success : OBJ        : COMPILE      ;
generators.register-standard testing.expect-failure : OBJ        : COMPILE_FAIL ;
generators.register-standard testing.expect-success : RUN_OUTPUT : RUN          ;
generators.register-standard testing.expect-failure : RUN_OUTPUT : RUN_FAIL     ;
generators.register-standard testing.expect-failure : EXE        : LINK_FAIL    ;
generators.register-standard testing.expect-success : EXE        : LINK         ;

# Generator which runs an EXE and captures output.
generators.register-standard testing.capture-output : EXE : RUN_OUTPUT ;

# Generator which creates a target if sources run successfully. Differs from RUN
# in that run output is not captured. The reason why it exists is that the 'run'
# rule is much better for automated testing, but is not user-friendly (see
# http://article.gmane.org/gmane.comp.lib.boost.build/6353).
generators.register-standard testing.unit-test : EXE : UNIT_TEST ;


# The action rules called by generators.

# Causes the 'target' to exist after bjam invocation if and only if all the
# dependencies were successfully built.
#
rule expect-success ( target : dependency + : requirements * )
{
    **passed** $(target) : $(dependency) ;
}


# Causes the 'target' to exist after bjam invocation if and only if all some of
# the dependencies were not successfully built.
#
rule expect-failure ( target : dependency + : properties * )
{
    local grist = [ MATCH ^<(.*)> : $(dependency:G) ] ;
    local marker = $(dependency:G=$(grist)*fail) ;
    (failed-as-expected) $(marker) ;
    FAIL_EXPECTED $(dependency) ;
    LOCATE on $(marker) = [ on $(dependency) return $(LOCATE) ] ;
    RMOLD $(marker) ;
    DEPENDS $(marker) : $(dependency) ;
    DEPENDS $(target) : $(marker) ;
    **passed** $(target) : $(marker) ;
}


# The rule/action combination used to report successful passing of a test.
#
rule **passed**
{
    remove-test-targets $(<) ;

    # Dump all the tests, if needed. We do it here, since dump should happen
    # only after all Jamfiles have been read, and there is no such place
    # currently defined (but there should be).
    if ! $(.dumped-tests) && ( --dump-tests in [ modules.peek : ARGV ] )
    {
        .dumped-tests = true ;
        dump-tests ;
    }

    # Force deletion of the target, in case any dependencies failed to build.
    RMOLD $(<) ;
}



# Used to create test files signifying passed tests.
#
actions **passed**
{
    echo passed > "$(<)"
}

# Used to create replacement object files that do not get created during tests
# that are expected to fail.
#
actions (failed-as-expected)
{
    echo failed as expected > "$(<)"
}


if [ os.name ] = VMS
{
    actions **passed**
    {
        PIPE WRITE SYS$OUTPUT "passed" > $(<:W)
    }

    actions (failed-as-expected)
    {
        PIPE WRITE SYS$OUTPUT "failed as expected" > $(<:W)
    }
}

rule run-path-setup ( target : source : properties * )
{
    # For testing, we need to make sure that all dynamic libraries needed by the
    # test are found. So, we collect all paths from dependency libraries (via
    # xdll-path property) and add whatever explicit dll-path user has specified.
    # The resulting paths are added to the environment on each test invocation.
    local dll-paths = [ feature.get-values <dll-path> : $(properties) ] ;
    dll-paths += [ feature.get-values <xdll-path> : $(properties) ] ;
    dll-paths += [ on $(source) return $(RUN_PATH) ] ;
    dll-paths = [ sequence.unique $(dll-paths) ] ;
    if $(dll-paths)
    {
        translate-to-os = path.native ;
        if [ os.name ] = VMS
        {
            translate-to-os = path.to-VMS ;
        }
        dll-paths = [ sequence.transform $(translate-to-os) : $(dll-paths) ] ;
        PATH_SETUP on $(target) = [ common.prepend-path-variable-command
            [ os.shared-library-path-variable ] : $(dll-paths) ] ;
    }
}


local argv = [ modules.peek : ARGV ] ;

toolset.flags testing.capture-output ARGS <testing.arg> ;
toolset.flags testing.capture-output INPUT_FILES <testing.input-file> ;
toolset.flags testing.capture-output LAUNCHER <testing.launcher> ;

.preserve-test-targets = on ;
if --remove-test-targets in [ modules.peek : ARGV ]
{
    .preserve-test-targets = off ;
}


# Runs executable 'sources' and stores stdout in file 'target'. Unless
# --preserve-test-targets command line option has been specified, removes the
# executable. The 'target-to-remove' parameter controls what should be removed:
#   - if 'none', does not remove anything, ever
#   - if empty, removes 'source'
#   - if non-empty and not 'none', contains a list of sources to remove.
#
rule capture-output ( target : source : properties * : targets-to-remove * )
{
    output-file on $(target) = $(target:S=.output) ;
    LOCATE on $(target:S=.output) = [ on $(target) return $(LOCATE) ] ;

    # The INCLUDES kill a warning about independent target...
    INCLUDES $(target) : $(target:S=.output) ;
    # but it also puts .output into dependency graph, so we must tell jam it is
    # OK if it cannot find the target or updating rule.
    NOCARE $(target:S=.output) ;

    # This has two-fold effect. First it adds input files to the dependency
    # graph, preventing a warning. Second, it causes input files to be bound
    # before target is created. Therefore, they are bound using SEARCH setting
    # on them and not LOCATE setting of $(target), as in other case (due to jam
    # bug).
    DEPENDS $(target) : [ on $(target) return $(INPUT_FILES) ] ;

    if $(targets-to-remove) = none
    {
        targets-to-remove = ;
    }
    else if ! $(targets-to-remove)
    {
        targets-to-remove = $(source) ;
    }

    run-path-setup $(target) : $(source) : $(properties) ;

    DISABLE_TEST_EXECUTION on $(target) = 0 ;
    if [ feature.get-values testing.execute : $(properties) ] = off
    {
        DISABLE_TEST_EXECUTION on $(target) = 1 ;
    }

    if [ feature.get-values preserve-test-targets : $(properties) ] = off
        || $(.preserve-test-targets) = off
    {
        rmtemp-sources $(target) : $(targets-to-remove) ;
        for local to-remove in $(targets-to-remove)
        {
            rmtemp-all-sources $(to-remove) ;
        }
    }

    if ! [ feature.get-values testing.launcher : $(properties) ]
    {
        ## On VMS set default launcher to MCR
        if [ os.name ] = VMS { LAUNCHER on $(target) = MCR ; }
    }
}

.types-to-remove = EXE OBJ ;

local rule remove-test-targets ( targets + )
{
    if $(.preserve-test-targets) = off
    {
        rmtemp-all-sources $(target) ;
    }
}

local rule rmtemp-all-sources ( target )
{
    local sources ;
    local action = [ on $(target) return $(.action) ] ;
    if $(action)
    {
        local action-sources = [ $(action).sources ] ;
        for local source in $(action-sources)
        {
            local source-type = [ $(source).type ] ;
            if $(source-type) in $(.types-to-remove)
            {
                sources += [ $(source).actual-name ] ;
            }
            else
            {
                # ECHO IGNORED: $(source) :: $(source-type) ;
            }
        }
        if $(sources)
        {
            rmtemp-sources $(target) : $(sources) ;
            for local source in $(sources)
            {
                rmtemp-all-sources $(source) ;
            }
        }
    }
}

local rule rmtemp-sources ( target : sources * )
{
    if $(sources)
    {
        TEMPORARY $(sources) ;
        # Set a second action on target that will be executed after capture
        # output action. The 'RmTemps' rule has the 'ignore' modifier so it is
        # always considered succeeded. This is needed for 'run-fail' test. For
        # that test the target will be marked with FAIL_EXPECTED, and without
        # 'ignore' successful execution will be negated and be reported as
        # failure. With 'ignore' we do not detect a case where removing files
        # fails, but it is not likely to happen.
        RmTemps $(target) : $(sources) ;
    }
}


if [ os.name ] = NT
{
    .STATUS        = %status% ;
    .SET_STATUS    = "set status=%ERRORLEVEL%" ;
    .RUN_OUTPUT_NL = "echo." ;
    .THEN          = "(" ;
    .EXIT_SUCCESS  = "0" ;
    .STATUS_0      = "%status% EQU 0 $(.THEN)" ;
    .STATUS_NOT_0  = "%status% NEQ 0 $(.THEN)" ;
    .VERBOSE       = "%verbose% EQU 1 $(.THEN)" ;
    .ENDIF         = ")" ;
    .SHELL_SET     = "set " ;
    .CATENATE      = type ;
    .CP            = copy ;
    .NULLIN        = ;
}
else if [ os.name ] = VMS
{
    local nl = "
" ;

    .STATUS        = "''status'" ;
    .SET_STATUS    = "status=$STATUS" ;
    .SAY           = "pipe write sys$output" ; ## not really echo
    .RUN_OUTPUT_NL = "$(.SAY) \"\"" ;
    .THEN          = "$(nl)then" ;
    .EXIT_SUCCESS  = "1" ;
    .SUCCESS       = "status .eq. $(.EXIT_SUCCESS) $(.THEN)" ;
    .STATUS_0      = "status .eq. 0 $(.THEN)" ;
    .STATUS_NOT_0  = "status .ne. 0 $(.THEN)" ;
    .VERBOSE       = "verbose .eq. 1 $(.THEN)" ;
    .ENDIF         = "endif" ;
    .SHELL_SET     = "" ;
    .CATENATE      = type ;
    .CP            = copy ;
    .NULLIN        = ;
}
else
{
    .STATUS        = "$status" ;
    .SET_STATUS    = "status=$?" ;
    .RUN_OUTPUT_NL = "echo" ;
    .THEN          = "; then" ;
    .EXIT_SUCCESS  = "0" ;
    .STATUS_0      = "test $status -eq 0 $(.THEN)" ;
    .STATUS_NOT_0  = "test $status -ne 0 $(.THEN)" ;
    .VERBOSE       = "test $verbose -eq 1 $(.THEN)" ;
    .ENDIF         = "fi" ;
    .SHELL_SET     = "" ;
    .CATENATE      = cat ;
    .CP            = cp ;
    .NULLIN        = "<" "/dev/null" ;
}


.VERBOSE_TEST = 0 ;
if --verbose-test in [ modules.peek : ARGV ]
{
    .VERBOSE_TEST = 1 ;
}


.RM = [ common.rm-command ] ;


actions capture-output bind INPUT_FILES output-file
{
    $(PATH_SETUP)
    $(.SHELL_SET)status=$(DISABLE_TEST_EXECUTION)
    if $(.STATUS_NOT_0)
        echo Skipping test execution due to testing.execute=off
        exit $(.EXIT_SUCCESS)
    $(.ENDIF)
    $(LAUNCHER) "$(>)" $(ARGS) "$(INPUT_FILES)" > "$(output-file)" 2>&1 $(.NULLIN)
    $(.SET_STATUS)
    $(.RUN_OUTPUT_NL) >> "$(output-file)"
    echo EXIT STATUS: $(.STATUS) >> "$(output-file)"
    if $(.STATUS_0)
        $(.CP) "$(output-file)" "$(<)"
    $(.ENDIF)
    $(.SHELL_SET)verbose=$(.VERBOSE_TEST)
    if $(.STATUS_NOT_0)
        $(.SHELL_SET)verbose=1
    $(.ENDIF)
    if $(.VERBOSE)
        echo ====== BEGIN OUTPUT ======
        $(.CATENATE) "$(output-file)"
        echo ====== END OUTPUT ======
    $(.ENDIF)
    exit $(.STATUS)
}


actions quietly updated ignore piecemeal together RmTemps
{
    $(.RM) "$(>)"
}

if [ os.name ] = VMS
{
    actions capture-output bind INPUT_FILES output-file
    {
        $(PATH_SETUP)
        $(.SHELL_SET)status=$(DISABLE_TEST_EXECUTION)
        if $(.STATUS_NOT_0)
            $(.SAY) "Skipping test execution due to testing.execute=off"
            exit "$(.EXIT_SUCCESS)"
        $(.ENDIF)
        !! Execute twice - first for status, second for output
        set noon
        pipe $(LAUNCHER) $(>:W) $(ARGS) $(INPUT_FILES:W) 2>NL: >NL:
        $(.SET_STATUS)
        pipe $(LAUNCHER) $(>:W) $(ARGS) $(INPUT_FILES:W) | type sys$input /out=$(output-file:W)
        set on
        !! Harmonize VMS success status with POSIX
        if $(.SUCCESS)
            $(.SHELL_SET)status="0"
        $(.ENDIF)
        $(.RUN_OUTPUT_NL) | append /new sys$input $(output-file:W)
        $(.SAY) "EXIT STATUS: $(.STATUS)" | append /new sys$input $(output-file:W)
        if $(.STATUS_0)
            $(.CP) $(output-file:W) $(<:W)
        $(.ENDIF)
        $(.SHELL_SET)verbose=$(.VERBOSE_TEST)
        if $(.STATUS_NOT_0)
            $(.SHELL_SET)verbose=1
        $(.ENDIF)
        if $(.VERBOSE)
            $(.SAY) "====== BEGIN OUTPUT ======"
            $(.CATENATE) $(output-file:W)
            $(.SAY) "====== END OUTPUT ======"
        $(.ENDIF)
        !! Harmonize VMS success status with POSIX on exit
        if $(.STATUS_0)
            $(.SHELL_SET)status="$(.EXIT_SUCCESS)"
        $(.ENDIF)
        exit "$(.STATUS)"
    }

    actions quietly updated ignore piecemeal together RmTemps
    {
        $(.RM) $(>:WJ=;*,);*
    }
}

.MAKE_FILE = [ common.file-creation-command ] ;

toolset.flags testing.unit-test LAUNCHER <testing.launcher> ;
toolset.flags testing.unit-test ARGS <testing.arg> ;


rule unit-test ( target : source : properties * )
{
    run-path-setup $(target) : $(source) : $(properties) ;

    if ! [ feature.get-values testing.launcher : $(properties) ]
    {
        ## On VMS set default launcher to MCR
        if [ os.name ] = VMS { LAUNCHER on $(target) = MCR ; }
    }
}


actions unit-test
{
    $(PATH_SETUP)
    $(LAUNCHER) "$(>)" $(ARGS) && $(.MAKE_FILE) "$(<)"
}

if [ os.name ] = VMS
{
    actions unit-test
    {
        $(PATH_SETUP)
        pipe $(LAUNCHER) $(>:W) $(ARGS) && $(.MAKE_FILE) $(<:W)
    }
}

IMPORT $(__name__) : compile compile-fail run run-fail link link-fail
    : : compile compile-fail run run-fail link link-fail ;


# This is a composing generator to support cases where a generator for the
# specified target constructs other targets as well. One such example is msvc's
# exe generator that constructs both EXE and PDB targets.
type.register TIME : time ;
generators.register-composing testing.time : : TIME ;


# Note that this rule may be called multiple times for a single target in case
# there are multiple actions operating on the same target in sequence. One such
# example are msvc exe targets first created by a linker action and then updated
# with an embedded manifest file by a separate action.
rule record-time ( target : source : start end user system clock )
{
    local src-string = [$(source:G=:J=",")"] " ;
    USER_TIME on $(target) += $(src-string)$(user) ;
    SYSTEM_TIME on $(target) += $(src-string)$(system) ;
    CLOCK_TIME on $(target) += $(src-string)$(clock) ;

    # We need the following variables because attempting to perform such
    # variable expansion in actions would not work due to quotes getting treated
    # as regular characters.
    USER_TIME_SECONDS on $(target) += $(src-string)$(user)" seconds" ;
    SYSTEM_TIME_SECONDS on $(target) += $(src-string)$(system)" seconds" ;
    CLOCK_TIME_SECONDS on $(target) += $(src-string)$(clock)" seconds" ;
}


# Support for generating timing information for any main target. To use
# declare a custom make target that uses the testing.time generator rule
# specified here. For example:
#
# make main.cpp : main_cpp.pro : @do-something ;
# time main.time : main.cpp ;
# actions do-something
# {
#     sleep 2 && echo "$(<)" > "$(<)"
# }
#
# The above will generate a "main.time", and echo to output, timing
# information for the action of source "main.cpp".


IMPORT testing : record-time : : testing.record-time ;


# Calling this rule requests that Boost Build time how long it takes to build
# the 'source' target and display the results both on the standard output and in
# the 'target' file.
#
rule time ( target : sources + : properties *  )
{
    # Set up rule for recording timing information.
    local action = [ on $(target) return $(.action) ] ;
    for local action.source in [ $(action).sources ]
    {
        # Yes, this uses the private "actual-name" of the target action.
        # But it's the only way to get at the real name of the sources
        # given the context of header scanners.
        __TIMING_RULE__ on [ $(action.source).actual-name ] = testing.record-time $(target) ;
    }

    # Make sure the sources get rebuilt any time we need to retrieve that
    # information.
    REBUILDS $(target) : $(sources) ;
}


actions time
{
    echo user: $(USER_TIME)
    echo system: $(SYSTEM_TIME)
    echo clock: $(CLOCK_TIME)

    echo user: $(USER_TIME_SECONDS) > "$(<)"
    echo system: $(SYSTEM_TIME_SECONDS) >> "$(<)"
    echo clock: $(CLOCK_TIME_SECONDS) >> "$(<)"
}

if [ os.name ] = VMS
{
    actions time
    {
        WRITE SYS$OUTPUT "user: ", "$(USER_TIME)"
        WRITE SYS$OUTPUT "system: ", "(SYSTEM_TIME)"
        WRITE SYS$OUTPUT "clock: ", "(CLOCK_TIME)"

        PIPE WRITE SYS$OUTPUT "user: ", "$(USER_TIME_SECONDS)" | TYPE SYS$INPUT /OUT=$(<:W)
        PIPE WRITE SYS$OUTPUT "system: ", "$(SYSTEM_TIME_SECONDS)" | APPEND /NEW SYS$INPUT $(<:W)
        PIPE WRITE SYS$OUTPUT "clock: ", "$(CLOCK_TIME_SECONDS)" | APPEND /NEW SYS$INPUT $(<:W)
    }
}
