B ›³ëbŒ ã@sèdZddlZddlmZmZddlmZddlZddl Zddl Zej j Z ej j Zej jZej jZej jZej jZej jZdadZGdd„dƒZgZdZd d „ZGd d „d eƒZGd d„deƒZ Gdd„deƒZ!dd„Z"Gdd„dƒZ#dS)a`Generic Taskmaster module for the SCons build engine. This module contains the primary interface(s) between a wrapping user interface and the SCons build engine. There are two key classes here: Taskmaster This is the main engine for walking the dependency graph and calling things to decide what does or doesn't need to be built. Task This is the base class for allowing a wrapping interface to decide what does or doesn't actually need to be done. The intention is for a wrapping interface to subclass this as appropriate for different types of behavior it may need. The canonical example is the SCons native Python interface, which has Task subclasses that handle its specific behavior, like printing "'foo' is up to date" when a top-level target doesn't need to be built, and handling the -c option by removing targets as its "build" action. There is also a separate subclass for suppressing this output when the -q option is used. The Taskmaster instantiates a Task object for each (set of) target(s) that it decides need to be evaluated and/or built. éN)ÚABCÚabstractmethod)ÚchainFc@seZdZdZdd„ZdS)ÚStatsaN A simple class for holding statistics about the disposition of a Node by the Taskmaster. If we're collecting statistics, each Node processed by the Taskmaster gets one of these attached, in which case the Taskmaster records its decision each time it processes the Node. (Ideally, that's just once per Node.) cCs.d|_d|_d|_d|_d|_d|_d|_dS)zp Instantiates a Taskmaster.Stats object, initializing all appropriate counters to zero. rN)Ú consideredÚalready_handledÚproblemÚ child_failedÚ not_builtÚ side_effectsÚbuild)Úself©rú/lib/python3.7/site-packages/SCons/Taskmaster.pyÚ__init__RszStats.__init__N)Ú__name__Ú __module__Ú __qualname__Ú__doc__rrrrrrJsrzp%(considered)3d %(already_handled)3d %(problem)3d %(child_failed)3d %(not_built)3d %(side_effects)3d %(build)3d cCs8x2ttdd„dD]}tt|jjjt|ƒƒqWdS)NcSst|ƒS)N)Ústr)ÚarrrÚjózdump_stats..)Úkey)ÚsortedÚ StatsNodesÚprintÚfmtÚ attributesÚstatsÚ__dict__r)ÚnrrrÚ dump_statsisr"c@sÀeZdZdZdd„Zd,dd„Zdd„Zd d „Zd d „Ze d d„ƒZ dd„Z dd„Z dd„Z e Zdd„Zdd„Zdd„Zdd„Zdd„ZeZdd „Zd!d"„Zd#d$„Zd-d&d'„Zd(d)„Zd*d+„Zd%S).ÚTaskaù SCons build engine abstract task class. This controls the interaction of the actual building of node and the rest of the engine. This is expected to handle all of the normally-customizable aspects of controlling a build, so any given application *should* be able to do what it wants by sub-classing this class and overriding methods as appropriate. If an application needs to customize something by sub-classing Taskmaster (or some other build engine class), we should first try to migrate that functionality into this class. Note that it's generally a good idea for sub-classes to call these methods explicitly to update state, etc., rather than roll their own interaction with Taskmaster from scratch. cCs$||_||_||_||_| ¡dS)N)ÚtmÚtargetsÚtopÚnodeÚ exc_clear)r r$r%r&r'rrrr€s z Task.__init__r'cCsd}||d||j |¡fS)Nz %-20s %s %s ú:)r$Ú trace_node)r Úmethodr'Z descriptionrrrrÚ trace_message‡szTask.trace_messagecCsdS)aà Hook to allow the calling interface to display a message. This hook gets called as part of preparing a task for execution (that is, a Node to be built). As part of figuring out what Node should be built next, the actual target list may be altered, along with a message describing the alteration. The calling interface can subclass Task and provide a concrete implementation of this method to see those messages. Nr)r ÚmessagerrrÚdisplay‹s z Task.displaycCsÚ|jj}|r | | d|j¡¡| ¡|jjrF| |jj¡d|j_|jd  ¡}|dkr`dS|  ¡xl|  ¡D]`}t r¢t d|ƒx|jD]}t d|ƒqŽW|  ¡x&|jD]}t rÆt d|ƒ|  ¡q²WqrWdS)a Called just before the task is executed. This is mainly intended to give the target Nodes a chance to unlink underlying files and make all necessary directories before the Action is actually called to build the targets. zTask.prepare()NrzPreparing target %s...z...with side-effect %s...z...Preparing side-effect %s...)r$ÚtraceÚwriter,r'Úexception_raiser-r.r%Ú get_executorÚprepareÚget_action_targetsÚ print_preparerr )r ÚTÚexecutorÚtÚsrrrr3˜s*      z Task.preparecCs|jS)z>Fetch the target being built or updated by this task. )r')r rrrÚ get_targetÆszTask.get_targetcCsdS)Nr)r rrrÚ needs_executeËszTask.needs_executec Csv|jj}|r | | d|j¡¡yžg}x"|jD]}| ¡s|jD]4}| ¡tkr(x|jD]}|  t ¡q@W|  t ¡q(WdS)z£ Called when the task has been successfully executed and the Taskmaster instance doesn't want to call the Node's callback methods. z!Task.executed_without_callbacks()N) r$r/r0r,r'r%Ú get_stateÚNODE_EXECUTINGr Ú set_stateÚ NODE_NO_STATEÚ NODE_EXECUTED)r r6r8Ú side_effectrrrÚexecuted_without_callbacksüs     zTask.executed_without_callbackscCsª|jj}|r | | d|j¡¡x„|jD]z}| ¡tkršx|jD]}|  t ¡q@W|  t ¡|j sj|  ¡| ¡| ¡ts¢t|dƒr|jjs¢| ¡q(| ¡q(WdS)aL Called when the task has been successfully executed and the Taskmaster instance wants to call the Node's callback methods. This may have been a do-nothing operation (to preserve build order), so we must check the node's state before deciding whether it was "built", in which case we call the appropriate Node method. In any event, we always call "visited()", which will handle any post-visit actions that must take place regardless of whether or not the target was an actual built target or a source Node. zTask.executed_with_callbacks()ÚoptionsN)r$r/r0r,r'r%rPrQr rRrSrTrBZ push_to_cacheZbuiltÚvisitedr5ÚhasattrrWÚdebug_includesÚrelease_target_info)r r6r8rUrrrÚexecuted_with_callbacks s"       zTask.executed_with_callbackscCs | ¡dS)zô Default action when a task fails: stop the build. Note: Although this function is normally invoked on nodes in the executing state, it might also be invoked on up-to-date nodes when using Configure(). N)Ú fail_stop)r rrrÚfailed/sz Task.failedcCsT|jj}|r | | d|j¡¡|j |jdd„¡|j ¡|jjg|_d|_ dS)aI Explicit stop-the-build failure. This sets failure status on the target nodes and all of their dependent parent nodes. Note: Although this function is normally invoked on nodes in the executing state, it might also be invoked on up-to-date nodes when using Configure(). zTask.failed_stop()cSs | t¡S)N)rRÚ NODE_FAILED)r!rrrrIrz Task.fail_stop..r<N) r$r/r0r,r'Úwill_not_buildr%ÚstopÚ current_topr&)r r6rrrr]9s   zTask.fail_stopcCs8|jj}|r | | d|j¡¡|j |jdd„¡dS)aM Explicit continue-the-build failure. This sets failure status on the target nodes and all of their dependent parent nodes. Note: Although this function is normally invoked on nodes in the executing state, it might also be invoked on up-to-date nodes when using Configure(). zTask.failed_continue()cSs | t¡S)N)rRr_)r!rrrrbrz$Task.fail_continue..N)r$r/r0r,r'r`r%)r r6rrrÚ fail_continueTs zTask.fail_continuecCsp|jj}|r | | d|j¡¡|jdd…|_x:|jD]0}| ¡ t ¡x|j D]}| ¡ t ¡qRWq8WdS)zÍ Marks all targets in a task ready for execution. This is used when the interface needs every target Node to be visited--the canonical example being the "scons -c" option. zTask.make_ready_all()N) r$r/r0r,r'r%Ú out_of_dateÚ disambiguaterRrQr )r r6r8r9rrrÚmake_ready_allds  zTask.make_ready_allc Cs6|jj}|r | | d|j¡¡g|_d}x†|jD]|}y*| ¡ ¡|  ¡ p\|j o\|  ¡}Wn8t k r˜}zt jj||j|jd‚Wdd}~XYnX|s2|j |¡d}q2W|rðxz|jD],}| t¡x|jD]}| ¡ t¡qÔWq¾WnBx@|jD]6}| ¡| t¡tsøt|dƒr&|jjsø| ¡qøWdS)z± Marks all targets in a task ready for execution if any target is not current. This is the default behavior for building only what's necessary. zTask.make_ready_current()F)r'ZerrstrÚfilenameNTrW)r$r/r0r,r'rdr%reÚ make_readyZ has_builderZ always_buildÚ is_up_to_dateÚEnvironmentErrorrFrGrKÚstrerrorrgr=rRrQr rXÚNODE_UP_TO_DATEr5rYrWrZr[)r r6Zneeds_executingr8rirNr9rrrÚmake_ready_currentus6     (      zTask.make_ready_currentc CsÂ|jj}|r | | d|j¡¡t|jƒ}|jj}i}x`|D]X}|jrh|r^| | d|d¡¡|  |¡x"|jD]}|  |d¡d||<qpWtƒ|_q|\}}d}YnXt|tƒrV| |¡‚n||ƒ |¡‚dS)zp Raises a pending exception that was recorded while getting a Task ready for execution. N)rEÚ ValueErrorÚ isinstancerLÚwith_traceback)r ÚexcÚexc_typerMÚ exc_tracebackrrrr| s   zTask._exception_raise)r')N)rrrrrr,r.r3r:rr;rOrVr\Úexecutedr^r]rcrfrmrhrvrEr(r}r{r|rrrrr#ns.  . -! ,K r#c@seZdZdd„ZdS)Ú AlwaysTaskcCsdS)a› Always returns True (indicating this Task should always be executed). Subclasses that need this behavior (as opposed to the default of only executing Nodes that are out of date w.r.t. their dependencies) can use this as follows: class MyTaskSubclass(SCons.Taskmaster.Task): needs_execute = SCons.Taskmaster.AlwaysTask.needs_execute Tr)r rrrr;(s zAlwaysTask.needs_executeN)rrrr;rrrrr…'sr…c@seZdZdd„ZdS)Ú OutOfDateTaskcCs|jd ¡tjjkS)zÔ Returns True (indicating this Task should be executed) if this Task's target state indicates it needs executing, which has already been determined by an earlier up-to-date check. r)r%rPrFÚNodeÚ executing)r rrrr;7szOutOfDateTask.needs_executeN)rrrr;rrrrr†6sr†cCsj|d|krdS| |d¡xF|djD]8}| |¡|d|dkrL|St||ƒrZ|S| ¡q*WdS)Néÿÿÿÿr)Úaddrpr=Ú find_cycleÚpop)ÚstackrXr!rrrr‹@s    r‹c@szeZdZdZgdddfdd„Zdd„Zdd„Zd d „Zd d „Zd d„Z dd„Z dd„Z dd„fdd„Z dd„Z dd„ZdS)Ú Taskmasterz8 The Taskmaster for walking the dependency DAG. NcCsh||_|dd…|_|j ¡g|_|dkr0t}||_|sBdd„}||_d|_||_|j |_ t ƒ|_ dS)NcSs|S)Nr)Úlrrrr\rz%Taskmaster.__init__..) Ú original_topÚtop_targets_leftÚreversertr†ÚtaskerÚorderr-r/Úfind_next_candidateÚnext_candidaternro)r r%r“r”r/rrrrSs zTaskmaster.__init__cCsŒy |j ¡Stk rYnXy|j ¡}Wntk rBdSX||_| ¡\}}|rˆ||_|j |¡|j |  |¡¡|j ¡}|S)aÍ Returns the next candidate Node for (potential) evaluation. The candidate list (really a stack) initially consists of all of the top-level (command line) targets provided when the Taskmaster was initialized. While we walk the DAG, visiting Nodes, all the children that haven't finished processing get pushed on to the candidate list. Each child can then be popped and examined in turn for whether *their* children are all up-to-date, in which case a Task will be created for their actual evaluation and potential building. Here is where we also allow candidate Nodes to alter the list of Nodes that should be examined. This is used, for example, when invoking SCons in a source directory. A source directory Node can return its corresponding build directory Node, essentially saying, "Hey, you really need to build this thing over here instead." N) rtrŒÚ IndexErrorr‘rbZ alter_targetsr-r=Úextendr”)r r'Zaltr-rrrr•cs     zTaskmaster.find_next_candidatecCs&x |jr |j}g|_| |¡qWdS)zü Stops Taskmaster processing by not returning a next candidate. Note that we have to clean-up the Taskmaster candidate list because the cycle detection depends on the fact all nodes have been processed somehow. N)rtr`)r rtrrrÚno_next_candidate‡s zTaskmaster.no_next_candidatecCsŽxˆ|jD]~}|jttfks0tt|ƒt|jfƒ‚t|jƒdksTtt|ƒt|jƒfƒ‚x0|jD]&}|j dks\tt|ƒt|ƒ|j fƒ‚q\WqWdS)aÜ Validate the content of the pending_children set. Assert if an internal error is found. This function is used strictly for debugging the taskmaster by checking that no invariants are violated. It is not used in normal operation. The pending_children set is used to detect cycles in the dependency graph. We call a "pending child" a child that is found in the "pending" state when checking the dependencies of its parent node. A pending child can occur when the Taskmaster completes a loop through a cycle. For example, let's imagine a graph made of three nodes (A, B and C) making a cycle. The evaluation starts at node A. The Taskmaster first considers whether node A's child B is up-to-date. Then, recursively, node B needs to check whether node C is up-to-date. This leaves us with a dependency graph looking like:: Next candidate Node A (Pending) --> Node B(Pending) --> Node C (NoState) ^ | | | +-------------------------------------+ Now, when the Taskmaster examines the Node C's child Node A, it finds that Node A is in the "pending" state. Therefore, Node A is a pending child of node C. Pending children indicate that the Taskmaster has potentially loop back through a cycle. We say potentially because it could also occur when a DAG is evaluated in parallel. For example, consider the following graph:: Node A (Pending) --> Node B(Pending) --> Node C (Pending) --> ... | ^ | | +----------> Node D (NoState) --------+ / Next candidate / The Taskmaster first evaluates the nodes A, B, and C and starts building some children of node C. Assuming, that the maximum parallel level has not been reached, the Taskmaster will examine Node D. It will find that Node C is a pending child of Node D. In summary, evaluating a graph with a cycle will always involve a pending child at one point. A pending child might indicate either a cycle or a diamond-shaped DAG. Only a fraction of the nodes ends-up being a "pending child" of another node. This keeps the pending_children set small in practice. We can differentiate between the two cases if we wait until the end of the build. At this point, all the pending children nodes due to a diamond-shaped DAG will have been properly built (or will have failed to build). But, the pending children involved in a cycle will still be in the pending state. The taskmaster removes nodes from the pending_children set as soon as a pending_children node moves out of the pending state. This also helps to keep the pending_children set small. rN) roÚstateÚ NODE_PENDINGrQÚAssertionErrorrÚ StateStringr>rprs)r r!rxrrrÚ_validate_pending_children•s F $ z%Taskmaster._validate_pending_childrencCsd|S)NzTaskmaster: %s r)r r-rrrr,ãszTaskmaster.trace_messagecCs dt| ¡|jtt|ƒƒfS)Nz<%-10s %-3s %s>)rrPrsÚreprr)r r'rrrr*æs zTaskmaster.trace_nodec Csd|_|j}|r$| d| d¡¡xì| ¡}|dkrT|rP| | d¡d¡dS| ¡}| ¡}tržt|j dƒsˆt ƒ|j _ t   |¡|j j }|jd|_nd}|rÀ| | d| |¡¡¡|tkrÔ| t¡n0|tkr|rî|jd|_|r(| | d¡¡q(| ¡}y | ¡}Wn®tk rnt ¡d}tj ||j¡}tjj|f|_|rj| | d ¡¡|Stk rÆ}z:t ¡|_|rœ|jd|_|r¶| | d |¡¡|Sd}~XYnXg} tƒ} g} d } xŽt | !¡|ƒD]|} |  ¡}|r| | d | | ¡¡¡|tkr,|   | ¡n$|tkrB|  "| ¡n|t#krPd } |t$krê|   | ¡qêW| r˜t%| ƒdkr†|  &¡|j' (| )| ¡¡| rîx| *¡D]}| t#¡q¨W|rÎ|j+d|_+|r(| | d| |¡¡¡q(| r’x^| D]V} |r|j,d|_,|j-|  .|¡|_-|rú| | d| |¡t/t0| ƒƒf¡¡qúW|r„x(| D] }| | d| |¡¡¡q`W|j1| B|_1q(d }x.| 2¡D]"}| ¡t$kr | 3|¡d }q W|rÞ|r(|j4d|_4q(|rð|j5d|_5|r| | d| |¡¡¡|SdS)aO Finds the next node that is ready to be built. This is *the* main guts of the DAG walk. We loop through the list of candidates, looking for something that has no un-built children (i.e., that is a leaf Node or has dependencies that are all leaf Nodes or up-to-date). Candidate Nodes are re-scanned (both the target Node itself and its sources, which are always scanned in the context of a given target) to discover implicit dependencies. A Node that must wait for some children to be built will be put back on the candidates list after the children have finished building. A Node that has been put back on the candidates list in this way may have itself (or its sources) re-scanned, in order to handle generated header files (e.g.) and the implicit dependencies therein. Note that this method does not do any signature calculation or up-to-date check itself. All of that is handled by the Task class. This is purely concerned with the dependency graph walk. NÚ zLooking for a node to evaluatezNo candidate anymore.rr<z) Considering node %s and its children:z! already handled (executed)z SystemExitz- exception %s while scanning children. Fz Tz ****** %s z% adjusted ref count: %s, child %sz- adding %s to the pending children set zEvaluating %s )6Ú ready_excr/r0r,r–rerPÚ CollectStatsrYrrrrr=rr*rSrRr›rr2Zget_all_childrenrCrDrErFrGrHrIrLrrnrZget_all_prerequisitesrŠr_rQr>r’rtr˜r”r4r r rsZadd_to_waiting_parentsrŸrroZget_action_side_effectsZadd_to_waiting_s_er r )r r6r'ršÚSr7ZchildrenrMrNZchildren_not_visitedZchildren_pendingZchildren_not_readyZchildren_failedZchildZ childstater!ZpcZwait_side_effectsZserrrÚ_find_next_ready_nodeësÐ                     "         z Taskmaster._find_next_ready_nodec Csœ| ¡}|dkrdS| ¡}|dkr(dS| ¡}| ||||jk|¡}y | ¡Wn,tk r~}zt ¡|_ Wdd}~XYnX|j r’|  |j ¡d|_ |S)zÌ Returns the next task to be executed. This simply asks for the next Node to be evaluated, and then wraps it in the specific Task subclass with which we were initialized. N) r¤r2Zget_all_targetsr“rrhrLrDrEr¡r})r r'r7ZtlistZtaskrNrrrÚ next_task­s   zTaskmaster.next_taskcCsdS)Nr)r!rrrrÐrzTaskmaster.c Csà|j}|j}t|ƒ}||}|rHx&|D]}| | d| |¡¡¡q&Wyxxrt|ƒr¼| ¡}||ƒ|j}tƒ|_||B}||}x6|D].} | j d| _ |rˆ| | d| | ¡¡¡qˆWqLWWnt k rÔYnX||_dS)z° Perform clean-up about nodes that will never be built. Invokes a user defined function on all of these nodes (including all of their parents). z6 removing node %s from the pending children set r<z8 removing parent %s from the pending children set N) r/rornr0r,r*r>rŒrprsÚKeyError) r ZnodesZ node_funcr6roZto_visitr!r'rwrxrrrr`Ðs0      zTaskmaster.will_not_buildcCs |j|_dS)z5 Stops the current build completely. N)r™r–)r rrrraüszTaskmaster.stopcCs–|js dSdd„|jDƒ}dd„|Dƒ}|s0dSd}xP|D]H\}}|rd|dd tt|ƒ¡d}q:|d |t|ƒt| ¡f}q:Wtj  |¡‚dS) z. Check for dependency cycles. NcSsg|]}|t|gtƒƒf‘qSr)r‹rn)Ú.0r!rrrú sz&Taskmaster.cleanup..cSs$g|]\}}|s| ¡tkr|‘qSr)rPrT)r§r'Úcyclerrrr¨ szFound dependency cycle(s): z z -> r z> Internal Error: no cycle found for node %s (%s) in state %s ) roÚjoinÚmaprrŸrrPrFrGrJ)r ZnclistZgenuine_cyclesZdescr'r©rrrÚcleanupszTaskmaster.cleanup)rrrrrr•r™ržr,r*r¤r¥r`rar¬rrrrrŽNs$NC#,rŽ)$rrDÚabcrrÚ itertoolsrZ SCons.ErrorsrFZ SCons.NodeZSCons.Warningsr‡rZno_staterSÚpendingr›rˆrQZ up_to_daterlr„rTr^r_r5r¢rrrr"r#r…r†r‹rŽrrrrÚ0s6 <