Fixes part of [4.8k weekly] [go_modules] go_modules exceptions

go_modules/lib/dependabot/go_modules/file_updater/go_mod_updater.rb

@@ -66,6 +66,12 @@ class GoModUpdater
           /Out of diskspace/
         ].freeze, T::Array[Regexp])
 
+        GO_LANG = "Go"
+
+        AMBIGUOUS_ERROR_MESSAGE = /ambiguous import: found package (?<package>.*) in multiple modules/
+
+        GO_VERSION_MISMATCH = /requires go (?<current_ver>.*) .*running go (?<req_ver>.*);/
+
         GO_MOD_VERSION = /^go 1\.\d+(\.\d+)?$/
 
         sig do
@@ -292,6 +298,8 @@ def substitute_all(substitutions)
           write_go_mod(body)
         end
 
+        # rubocop:disable Metrics/AbcSize
+        # rubocop:disable Metrics/PerceivedComplexity
         sig { params(stderr: String).returns(T.noreturn) }
         def handle_subprocess_error(stderr) # rubocop:disable Metrics/AbcSize
           stderr = stderr.gsub(Dir.getwd, "")
@@ -323,10 +331,21 @@ def handle_subprocess_error(stderr) # rubocop:disable Metrics/AbcSize
             raise Dependabot::OutOfDisk.new, error_message
           end
 
+          if (matches = stderr.match(AMBIGUOUS_ERROR_MESSAGE))
+            raise Dependabot::DependencyFileNotResolvable, matches[:package]
+          end
+
+          if (matches = stderr.match(GO_VERSION_MISMATCH))
+            raise Dependabot::ToolVersionNotSupported.new(GO_LANG, T.must(matches[:current_ver]),
+                                                          T.must(matches[:req_ver]))
+          end
+
           # We don't know what happened so we raise a generic error
           msg = stderr.lines.last(10).join.strip
           raise Dependabot::DependabotError, msg
         end
+        # rubocop:enable Metrics/AbcSize
+        # rubocop:enable Metrics/PerceivedComplexity
 
         sig { params(message: String, regex: Regexp).returns(String) }
         def filter_error_message(message:, regex:)

go_modules/spec/dependabot/go_modules/file_updater/go_mod_updater_spec.rb

@@ -953,6 +953,35 @@
           expect(error.message).to include("write error. Out of diskspace")
         end
       end
+
+      it "detects 'ambiguous package'" do
+        stderr = <<~ERROR
+          go: downloading google.golang.org/grpc v1.70.0
+          go: github.com/terraform-linters/tflint imports
+                  github.com/terraform-linters/tflint/cmd imports
+                  github.com/terraform-linters/tflint-ruleset-terraform/rules imports
+                  github.com/hashicorp/go-getter imports
+                  cloud.google.com/go/storage imports
+                  google.golang.org: ambiguous import: found package google.golang.org/grpc/stats/otl in multiple modules:
+                  google.golang.org/grpc v1.69.2 (/home/dependabot/go/pkg/mod/stats/opentelemetry)
+        ERROR
+
+        expect do
+          updater.send(:handle_subprocess_error, stderr)
+        end.to raise_error(Dependabot::DependencyFileNotResolvable)
+      end
+
+      it "detects 'ToolVersionNotSupported'" do
+        stderr = <<~ERROR
+          go: downloading google.golang.org/grpc v1.67.3
+          go: downloading google.golang.org/grpc v1.70.0
+          go: google.golang.org/grpc/stats/[email protected] requires go >= 1.22.7 (running go 1.22.5; CUAIN=local+auto)
+        ERROR
+
+        expect do
+          updater.send(:handle_subprocess_error, stderr)
+        end.to raise_error(Dependabot::ToolVersionNotSupported)
+      end
     end
   end
 end