Further improve message by reporting the requiring bazel module

Author: HoloRin

bzlmod/erlang_package.bzl

@@ -13,6 +13,7 @@ load(
 )
 
 HexPackage = provider(fields = [
+    "module",
     "name",
     "version",
     "sha256",
@@ -24,6 +25,7 @@ HexPackage = provider(fields = [
 ])
 
 GitPackage = provider(fields = [
+    "module",
     "name",
     "version",
     "remote",
@@ -41,7 +43,7 @@ def log(ctx, msg):
 
 def hex_tree(
         ctx,
-        otp_installation_names = None,
+        module = None,
         name = None,
         version = None):
     log(ctx, "Fetching release info for {}@{} from hex.pm".format(name, version))
@@ -57,6 +59,7 @@ def hex_tree(
             requirements.append(props)
 
     return HexPackage(
+        module = module,
         name = name,
         version = version,
         sha256 = sha256,
@@ -69,13 +72,14 @@ def hex_tree(
 
 def hex_package(
         ctx,
-        otp_installation_names = None,
+        module = None,
         name = None,
         version = None,
         sha256 = None,
         build_file_content = None,
         patch_cmds = None):
     return HexPackage(
+        module = module,
         name = name,
         version = version,
         sha256 = sha256,
@@ -96,7 +100,7 @@ def _infer_app_name(remote):
 
 def git_package(
         ctx,
-        otp_installation_names = None,
+        module = None,
         dep = None):
     if dep.remote != "" and dep.repository != "":
         fail("'remote' and 'repository' are mutually exclusive options")
@@ -121,6 +125,7 @@ def git_package(
         version = dep.branch
 
     return GitPackage(
+        module = module,
         name = name,
         version = version,
         remote = remote,
@@ -145,6 +150,7 @@ def without_requirement(name, package):
                 new_requirements.append(r)
 
         return HexPackage(
+            module = package.module,
             name = package.name,
             version = package.version,
             sha256 = package.sha256,

bzlmod/extensions.bzl

@@ -87,10 +87,12 @@ def _newest(a, b):
     a_version = version_from_string(a.version)
     b_version = version_from_string(b.version)
     if a_version == None or b_version == None:
-        fail("A version of {} & {} for {} cannot be resolved".format(
-            a.version,
-            b.version,
-            a.name,
+        fail("Version {dep_name}@{a_version} (required by {a_module}) & {dep_name}@{b_version} (required by {b_module}) cannot be resolved".format(
+            dep_name = a.name,
+            a_version = a.version,
+            a_module = a.module.name,
+            b_version = b.version,
+            b_module = b.module.name,
         ))
     elif lt(a_version, b_version):
         return b
@@ -120,12 +122,14 @@ def _erlang_package(ctx):
         for dep in mod.tags.hex_package_tree:
             packages.append(hex_tree(
                 ctx,
+                module = mod,
                 name = dep.name,
                 version = dep.version,
             ))
         for dep in mod.tags.hex_package:
             packages.append(hex_package(
                 ctx,
+                module = mod,
                 name = dep.name,
                 version = dep.version,
                 sha256 = dep.sha256,
@@ -135,6 +139,7 @@ def _erlang_package(ctx):
         for dep in mod.tags.git_package:
             packages.append(git_package(
                 ctx,
+                module = mod,
                 dep = dep,
             ))