Streamline CompUnit::PrecompilationUnit.is-up-to-date a bit

- use binding where possible
- remove unnecessary temporary variables
- some code esthetics

src/core.c/CompUnit/PrecompilationUnit.pm6

@@ -52,23 +52,33 @@ role CompUnit::PrecompilationUnit {
     method source-checksum(--> Str:D) { ... }
     method bytecode-handle(--> IO::Handle:D) { ... }
     method close(--> Nil) { ... }
-    method is-up-to-date(CompUnit::PrecompilationDependency $dependency, Bool :$check-source --> Bool) {
-        my $RMD = $*RAKUDO_MODULE_DEBUG;
-        if $check-source { # a repo changed, so maybe it's a change in our source file
-            my $source-checksum = $.source-checksum;
 
-            my $srcIO = CompUnit::RepositoryRegistry.file-for-spec($dependency.src) // $dependency.src.IO;
-            return False unless $srcIO and $srcIO.e;
+    method is-up-to-date(
+      CompUnit::PrecompilationDependency $dependency,
+      Bool :$check-source
+    --> Bool:D) {
+        my $RMD := $*RAKUDO_MODULE_DEBUG;
+
+        # a repo changed, so maybe it's a change in our source file
+        if $check-source {
+            my $srcIO :=
+              CompUnit::RepositoryRegistry.file-for-spec($dependency.src)
+              // $dependency.src.IO;
+            return False unless $srcIO.e;
+
+            my $current-source-checksum :=
+              nqp::sha1($srcIO.slurp(:enc<iso-8859-1>));
 
-            my $current-source-checksum := nqp::sha1($srcIO.slurp(:enc<iso-8859-1>).Str);
             $RMD(
                 "$.path\nspec: $dependency.spec()\nsource: $srcIO\n"
-                ~ "source-checksum: $source-checksum\ncurrent-source-checksum: $current-source-checksum"
+                ~ "source-checksum: $.source-checksum\ncurrent-source-checksum: $current-source-checksum"
             ) if $RMD;
-            return False if $source-checksum ne $current-source-checksum;
+
+            return False if $.source-checksum ne $current-source-checksum;
         }
 
-        $RMD("dependency checksum $dependency.checksum() unit: $.checksum()") if $RMD;
+        $RMD("dependency checksum $dependency.checksum() unit: $.checksum()")
+          if $RMD;
 
         $.checksum eq $dependency.checksum
     }