libstore: remove Goal::key

this was a debugging aid from day one that should not have any impact on
build semantics, and if it *does* have an impact on build semantics then
build semantics are seriously broken. keeping the order imposed by these
keys will be impossible once we let a real event loop schedule our jobs.

Change-Id: I5c313324e1f213ab6453d82f41ae5e59de809a5b

7 files changed, 1 insertions, 44 deletions

diff --git a/src/libstore/build/derivation-goal.cc b/src/libstore/build/derivation-goal.cc
index 037b4fb10..f28285ad8 100644
--- a/src/libstore/build/derivation-goal.cc
+++ b/src/libstore/build/derivation-goal.cc
@@ -113,16 +113,6 @@ DerivationGoal::~DerivationGoal() noexcept(false)
 }
 
 
-std::string DerivationGoal::key()
-{
-    /* Ensure that derivations get built in order of their name,
-       i.e. a derivation named "aardvark" always comes before
-       "baboon". And substitution goals always happen before
-       derivation goals (due to "b$"). */
-    return "b$" + std::string(drvPath.name()) + "$" + worker.store.printStorePath(drvPath);
-}
-
-
 void DerivationGoal::killChild()
 {
     hook.reset();
diff --git a/src/libstore/build/derivation-goal.hh b/src/libstore/build/derivation-goal.hh
index b1311bd7e..6e8e979d3 100644
--- a/src/libstore/build/derivation-goal.hh
+++ b/src/libstore/build/derivation-goal.hh
@@ -247,8 +247,6 @@ struct DerivationGoal : public Goal
 
     Finished timedOut(Error && ex);
 
-    std::string key() override;
-
     kj::Promise<Result<WorkResult>> work() noexcept override;
 
     /**
diff --git a/src/libstore/build/drv-output-substitution-goal.cc b/src/libstore/build/drv-output-substitution-goal.cc
index 923cbba58..846268a3a 100644
--- a/src/libstore/build/drv-output-substitution-goal.cc
+++ b/src/libstore/build/drv-output-substitution-goal.cc
@@ -166,13 +166,6 @@ try {
     return {std::current_exception()};
 }
 
-std::string DrvOutputSubstitutionGoal::key()
-{
-    /* "a$" ensures substitution goals happen before derivation
-       goals. */
-    return "a$" + std::string(id.to_string());
-}
-
 kj::Promise<Result<Goal::WorkResult>> DrvOutputSubstitutionGoal::work() noexcept
 {
     return (this->*state)(slotToken.valid());
diff --git a/src/libstore/build/drv-output-substitution-goal.hh b/src/libstore/build/drv-output-substitution-goal.hh
index 805b65bfa..543fa7ed4 100644
--- a/src/libstore/build/drv-output-substitution-goal.hh
+++ b/src/libstore/build/drv-output-substitution-goal.hh
@@ -74,8 +74,6 @@ public:
     kj::Promise<Result<WorkResult>> outPathValid(bool inBuildSlot) noexcept;
     kj::Promise<Result<WorkResult>> finished() noexcept;
 
-    std::string key() override;
-
     kj::Promise<Result<WorkResult>> work() noexcept override;
 
     JobCategory jobCategory() const override {
diff --git a/src/libstore/build/goal.cc b/src/libstore/build/goal.cc
index 5f0ed485c..957bc2aaf 100644
--- a/src/libstore/build/goal.cc
+++ b/src/libstore/build/goal.cc
@@ -6,13 +6,6 @@
 namespace nix {
 
 
-bool CompareGoalPtrs::operator() (const GoalPtr & a, const GoalPtr & b) const {
-    std::string s1 = a->key();
-    std::string s2 = b->key();
-    return s1 < s2;
-}
-
-
 void Goal::trace(std::string_view s)
 {
     debug("%1%: %2%", name, s);
diff --git a/src/libstore/build/goal.hh b/src/libstore/build/goal.hh
index f808be160..4436e44b1 100644
--- a/src/libstore/build/goal.hh
+++ b/src/libstore/build/goal.hh
@@ -22,14 +22,10 @@ class Worker;
  */
 typedef std::shared_ptr<Goal> GoalPtr;
 
-struct CompareGoalPtrs {
-    bool operator() (const GoalPtr & a, const GoalPtr & b) const;
-};
-
 /**
  * Set of goals.
  */
-typedef std::set<GoalPtr, CompareGoalPtrs> Goals;
+typedef std::set<GoalPtr> Goals;
 
 /**
  * Used as a hint to the worker on how to schedule a particular goal. For example,
@@ -167,8 +163,6 @@ public:
         return name;
     }
 
-    virtual std::string key() = 0;
-
     virtual void cleanup() { }
 
     /**
diff --git a/src/libstore/build/substitution-goal.hh b/src/libstore/build/substitution-goal.hh
index cef3a4c5c..5411afa01 100644
--- a/src/libstore/build/substitution-goal.hh
+++ b/src/libstore/build/substitution-goal.hh
@@ -90,15 +90,6 @@ public:
     );
     ~PathSubstitutionGoal();
 
-    /**
-     * We prepend "a$" to the key name to ensure substitution goals
-     * happen before derivation goals.
-     */
-    std::string key() override
-    {
-        return "a$" + std::string(storePath.name()) + "$" + worker.store.printStorePath(storePath);
-    }
-
     kj::Promise<Result<WorkResult>> work() noexcept override;
 
     /**