issue 1025: a context naming the module's own repository is its own build source (ADR 0420 §4)

internal/inventory/builds.go

@@ -428,7 +428,8 @@ func (i *Inventory) ReadRepositories(ctx context.Context) (map[string][]ReadRepo
 	}
 
 	rows, err := i.store.Pool().Query(ctx,
-		`select distinct on (module) module, built_contexts, build_sources, coalesce(asked, at)
+		`select distinct on (module) module, built_contexts, build_sources, coalesce(asked, at),
+		        (select source from module where module.name = build.module)
 		   from build
 		  where module is not null and module <> '' and failed = ''
 		  order by module, `+newestRequestFirst)
@@ -442,7 +443,8 @@ func (i *Inventory) ReadRepositories(ctx context.Context) (map[string][]ReadRepo
 		var module string
 		var raw, rawSources []byte
 		var built time.Time
-		if err := rows.Scan(&module, &raw, &rawSources, &built); err != nil {
+		var own *string
+		if err := rows.Scan(&module, &raw, &rawSources, &built, &own); err != nil {
 			return nil, err
 		}
 		var of []ReadRepository
@@ -462,6 +464,9 @@ func (i *Inventory) ReadRepositories(ctx context.Context) (map[string][]ReadRepo
 			sources, whole = nil, "a newer build of it failed"
 		}
 		of = WithBuildSources(of, sources)
+		if own != nil {
+			of = OwnRepositoryAsOwn(of, *own)
+		}
 		if whole != "" {
 			of = append(of, ReadRepository{Own: true, Whole: whole})
 		}
@@ -498,6 +503,57 @@ func WithBuildSources(read []ReadRepository, sources []BuildSource) []ReadReposi
 	return out
 }
 
+// OwnRepositoryAsOwn reads a context that names the module's own registered repository, with the paths its
+// build read there, as the module's own build source (novox/hq ADR 0420 §4): a change to the program it
+// compiles moves the module, as one in its own directory does. A context of that repository that said
+// no paths stays a context read, whole.
+func OwnRepositoryAsOwn(read []ReadRepository, repository string) []ReadRepository {
+	if repository == "" {
+		return read
+	}
+	out := make([]ReadRepository, 0, len(read))
+	var moved []ReadRepository
+	for _, r := range read {
+		if !r.Own && len(r.Paths) > 0 && r.Repository != "" && namesRepository(repository, r.Repository) {
+			moved = append(moved, r)
+			continue
+		}
+		out = append(out, r)
+	}
+	if len(moved) == 0 {
+		return read
+	}
+	// One entry of its own: ownSource reads the first that has paths.
+	at := -1
+	for k := range out {
+		if out[k].Own && len(out[k].Paths) > 0 {
+			at = k
+			break
+		}
+	}
+	if at < 0 {
+		out = append(out, ReadRepository{Own: true})
+		at = len(out) - 1
+	}
+	for _, r := range moved {
+		out[at].Paths = append(append([]string(nil), out[at].Paths...), r.Paths...)
+		if out[at].Ref == "" {
+			out[at].Ref = r.Ref
+		}
+	}
+	return out
+}
+
+// namesRepository is whether a context's repository, as owner/name, is the registered one, which may be
+// spelled as the URL it was cloned from.
+func namesRepository(registered, named string) bool {
+	trim := func(s string) string {
+		return strings.TrimSuffix(strings.TrimRight(strings.ToLower(strings.TrimSpace(s)), "/"), ".git")
+	}
+	reg, name := trim(registered), trim(named)
+	return reg == name || strings.HasSuffix(reg, "/"+name)
+}
+
 // manifestOrNil keeps the difference between "declared nothing" and "predates this being kept".
 //
 // A build recorded before the mesh kept manifests has no manifest, and that is not the same as one