Get rid of DerivationType::Impure

The point of making `DerivationType::ContentAddressed` a record (and
derivation type no longer an enum) was that we already handled this case
and didn't need a new variant.

src/libstore/build/derivation-goal.cc

@@ -476,9 +476,6 @@ void DerivationGoal::inputsRealised()
                        drvs. */
                     : true);
             },
-            [&](const DerivationType::Impure &) {
-                return true;
-            }
         }, drvType.raw());
 
         if (resolveDrv && !fullDrv.inputDrvs.empty()) {

src/libstore/derivations.cc

@@ -53,9 +53,6 @@ bool DerivationType::isCA() const
         [](const ContentAddressed & ca) {
             return true;
         },
-        [](const Impure &) {
-            return true;
-        },
     }, raw());
 }
 
@@ -68,9 +65,6 @@ bool DerivationType::isFixed() const
         [](const ContentAddressed & ca) {
             return ca.fixed;
         },
-        [](const Impure &) {
-            return false;
-        },
     }, raw());
 }
 
@@ -83,9 +77,6 @@ bool DerivationType::hasKnownOutputPaths() const
         [](const ContentAddressed & ca) {
             return ca.fixed;
         },
-        [](const Impure &) {
-            return false;
-        },
     }, raw());
 }
 
@@ -99,9 +90,6 @@ bool DerivationType::isSandboxed() const
         [](const ContentAddressed & ca) {
             return ca.sandboxed;
         },
-        [](const Impure &) {
-            return false;
-        },
     }, raw());
 }
 
@@ -113,10 +101,7 @@ bool DerivationType::isPure() const
             return true;
         },
         [](const ContentAddressed & ca) {
-            return true;
-        },
-        [](const Impure &) {
-            return false;
+            return ca.sandboxed || ca.fixed;
         },
     }, raw());
 }
@@ -396,7 +381,7 @@ std::string Derivation::unparse(const Store & store, bool maskOutputs,
                 s += ','; printUnquotedString(s, "");
                 s += ','; printUnquotedString(s, "");
             },
-            [&](const DerivationOutputImpure & doi) {
+            [&](const DerivationOutput::Impure & doi) {
                 // FIXME
                 s += ','; printUnquotedString(s, "");
                 s += ','; printUnquotedString(s, makeFileIngestionPrefix(doi.method) + printHashType(doi.hashType));
@@ -557,7 +542,10 @@ DerivationType BasicDerivation::type() const
         && floatingCAOutputs.empty()
         && deferredIAOutputs.empty()
         && !impureOutputs.empty())
-        return DerivationType::Impure { };
+        return DerivationType::ContentAddressed {
+            .sandboxed = false,
+            .fixed = false,
+        };
 
     throw Error("can't mix derivation output types");
 }
@@ -638,9 +626,6 @@ DrvHash hashDerivationModulo(Store & store, const Derivation & drv, bool maskOut
                 ? DrvHash::Kind::Regular
                 : DrvHash::Kind::Deferred;
         },
-        [](const DerivationType::Impure &) -> DrvHash::Kind {
-            return DrvHash::Kind::Deferred;
-        }
     }, drv.type().raw());
 
     std::map<std::string, StringSet> inputs2;

src/libstore/derivations.hh

@@ -106,21 +106,16 @@ struct DerivationType_ContentAddressed {
     bool fixed;
 };
 
-struct DerivationType_Impure {
-};
-
 typedef std::variant<
     DerivationType_InputAddressed,
-    DerivationType_ContentAddressed,
-    DerivationType_Impure
+    DerivationType_ContentAddressed
 > _DerivationTypeRaw;
 
 struct DerivationType : _DerivationTypeRaw {
     using Raw = _DerivationTypeRaw;
     using Raw::Raw;
     using InputAddressed = DerivationType_InputAddressed;
     using ContentAddressed = DerivationType_ContentAddressed;
-    using Impure = DerivationType_Impure;
 
     /* Do the outputs of the derivation have paths calculated from their content,
        or from the derivation itself? */