Add crate configuration values to build hash inputs

src/alire/alire-builds-hashes.adb

@@ -1,3 +1,4 @@
+with Alire.Crate_Configuration.Hashes;
 with Alire.Directories;
 with Alire.Environment;
 with Alire.GPR;
@@ -172,17 +173,27 @@ package body Alire.Builds.Hashes is
             end loop;
          end Add_Environment;
 
+         -----------------------
+         -- Add_Configuration --
+         -----------------------
+
+         procedure Add_Configuration is
+         begin
+            Crate_Configuration.Hashes.Add_From
+              (Config => Root.Configuration,
+               Rel    => Rel,
+               Add    => Add'Access);
+         end Add_Configuration;
+
       begin
          Trace.Debug ("   build hashing: " & Rel.Milestone.TTY_Image);
 
          --  Add individual contributors to the hash input
-         Add_Profile;
-         Add_Externals;
-         Add_Environment;
-         Add_Compiler;
-
-         --  Configuration variables
-         --  TBD
+         Add_Profile;       -- Build profile
+         Add_Externals;     -- GPR externals
+         Add_Environment;   -- Environment variables
+         Add_Compiler;      -- Compiler version
+         Add_Configuration; -- Crate configuration variables
 
          --  Dependencies recursive hash? Since a crate can use a dependency
          --  config spec, it is possible in the worst case for a crate to
@@ -213,6 +224,8 @@ package body Alire.Builds.Hashes is
       Environment.Load (Context, Root, For_Hashing => True);
       Env := Context.Get_All;
 
+      Root.Configuration.Ensure_Complete;
+
       for Rel of Root.Solution.Releases loop
          if Root.Requires_Build_Sync (Rel) then
             Compute (Rel);

src/alire/alire-crate_configuration-hashes.adb

@@ -0,0 +1,42 @@
+with Alire.Errors;
+
+package body Alire.Crate_Configuration.Hashes is
+
+   procedure Add_From (Config : Global_Config;
+                       Rel    : Releases.Release;
+                       Add    : access procedure (Kind, Key, Value : String))
+   is
+   begin
+      --  We could iterate over Config contents, but by relying on the release
+      --  reported variables we ensure nothing is amiss during hashing.
+
+      for Untyped of Rel.Config_Variables loop
+         declare
+            Def : constant Properties.Configurations.Config_Type_Definition :=
+                    Properties.Configurations.Config_Type_Definition (Untyped);
+            Key : constant String :=
+                    Crate_Configuration.Key (Rel.Name, Def.Name);
+         begin
+            if not Config.Var_Map.Contains (+Key) then
+               raise Program_Error
+                 with Errors.Set
+                   ("Incomplete configuration during hashing, missing value "
+                    & "for: " & Key);
+            end if;
+
+            if not Def.Valid (Config.Var_Map (+Key).Value) then
+               raise Program_Error
+                 with Errors.Set ("Invalid config value during hashing: "
+                                  & Def.Image);
+            end if;
+
+            Add (Kind  => "config",
+                 Key   => Key,
+                 Value =>
+                   Properties.Configurations.Image
+                     (Config.Var_Map (+Key).Value));
+         end;
+      end loop;
+   end Add_From;
+
+end Alire.Crate_Configuration.Hashes;

src/alire/alire-crate_configuration-hashes.ads

@@ -0,0 +1,10 @@
+with Alire.Releases;
+
+package Alire.Crate_Configuration.Hashes is
+
+   procedure Add_From (Config : Global_Config;
+                       Rel    : Releases.Release;
+                       Add    : access procedure (Kind, Key, Value : String));
+   --  Add configuration values of the given crate to the build hash input
+
+end Alire.Crate_Configuration.Hashes;

src/alire/alire-crate_configuration.adb

@@ -734,6 +734,13 @@ package body Alire.Crate_Configuration is
       TIO.Close (File);
    end Generate_C_Config;
 
+   ---------
+   -- Key --
+   ---------
+
+   function Key (Crate : Crate_Name; Var_Name : String) return String
+   is (To_Lower_Case (Crate.As_String & "." & Var_Name));
+
    --------------------
    -- Add_Definition --
    --------------------
@@ -744,7 +751,7 @@ package body Alire.Crate_Configuration is
    is
       Type_Name_Lower : constant String := To_Lower_Case (Type_Def.Name);
 
-      Name : constant Unbounded_String := +(+Crate & "." & Type_Name_Lower);
+      Name : constant Unbounded_String := +Key (Crate, Type_Def.Name);
    begin
 
       if Is_Reserved_Name (Type_Name_Lower) then

src/alire/alire-crate_configuration.ads

@@ -172,4 +172,7 @@ private
                                 Filepath : Absolute_Path;
                                 Version  : String);
 
+   function Key (Crate : Crate_Name; Var_Name : String) return String;
+   --  Keys in the var map are normalized as "crate.var" lowercased
+
 end Alire.Crate_Configuration;

testsuite/fixtures/toolchain_index/cr/crate_real/crate_real-1.0.0.toml

@@ -4,7 +4,7 @@ version = "1.0.0"
 maintainers = ["[email protected]"]
 maintainers-logins = ["mylogin"]
 
-# Externals and environment used to track build hash generation immutability
+# Externals, environment, config used to track build hash generation immutability
 
 [gpr-externals]
 foo = ""
@@ -15,6 +15,9 @@ bar = "foo"
 [environment]
 BAZ.set = "foo"
 
+[configuration.variables]
+Var1={type="Boolean", default=true}
+
 [origin]
 url = "file:../../../crates/libhello_1.0.0.tgz"
 hashes = ["sha512:99fa3a55540d0655c87605b54af732f76a8a363015f183b06e98aa91e54c0e69397872718c5c16f436dd6de0fba506dc50c66d34a0e5c61fb63cb01fa22f35ac"]

testsuite/tests/build/hashes/hashing-inputs/test.py

@@ -35,6 +35,7 @@
 # profile, compiler version.
 
 assert_eq(
+    'config:libhello.var1=true\n'            # crate config var
     'environment:TEST_ENV=myenv\n'           # plain env var set
     'external:TEST_FREEFORM_UNSET=default\n' # declared unset GPR external
     'external:TEST_GPR_EXTERNAL=gpr_ext_B\n' # declared set GPR external

testsuite/tests/dockerized/misc/default-cache/test.py

@@ -39,7 +39,7 @@
 # We hardcode this hash so we detect unwilling changes to our hashing scheme.
 # Every time this hash changes we must know the reason (changes in the hashing
 # procedures)
-hash = "1a29f0454348e767e78ac6912c7409b374b7bf650e81396c8a8750797ae073eb"
+hash = "d56fceceba3a7deaa9df1a9b43afa4fb9c643bf5245b335cc12ba0ae4df15682"
 assert \
     os.path.isdir(f"{base}/builds/crate_real_1.0.0_filesystem_{hash}"), \
     f"Shared build not found at the expected location: f{contents(base)}"