Add ability to select goal based on push in DSL

[johnsonr]

Adds a setGoalsWhen method to GoalSetter that allows choosing goals based on the push invocation. This combines with the recent introduction of stateful push invocations to allow previously computed state to be used in both goal choice and goal selection.

The following example precomputes phases, attaches them as state to the invocation, and then chooses them on goal setting:

interface Analyzed {
    interpretation: Interpretation;
    phases: CiPhases;
}

sdm.withPushRules(
        // Attach facts to the invocation
        attachFacts<Analyzed>(async pu => {
            const interpretation = await analyzer.interpret(pu.project);
            const phases = createPhases(interpretation);
            return { interpretation, phases };
        }),
       // Choose and set goals based on introduced state
        onAnyPush<StatefulPushListenerInvocation<Analyzed>>()
            .setGoalsWhen(pu => pu.facts.phases.checkGoals),
        whenPushSatisfies<StatefulPushListenerInvocation<Analyzed>>(
            async pu => !!pu.facts.phases.buildGoals)
            .setGoalsWhen(pu => pu.facts.phases.buildGoals),
        whenPushSatisfies<StatefulPushListenerInvocation<Analyzed>>(
            async pu => !!pu.facts.phases.testGoals)
            .setGoalsWhen(pu => pu.facts.phases.testGoals),
    );

This change is backward compatible.

In this case the GoalSetter does not work as a StaticPushMapping, making it impossible to predict all goals that will be set.

[cdupuis]

LGTM

[atomist-bot]

Pull request auto merged by Atomist.

• 1 approved review by @cdupuis
• 2 successful checks

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