Merge pull request #311 from okp4/feat/source-file-predicate

🧠 Logic: 🗂️ source_file/1 predicate

Makefile

@@ -403,6 +403,7 @@ mock: ## Generate all the mocks (for tests)
 	@echo "${COLOR_CYAN} 🧱 Generating all the mocks${COLOR_RESET}"
 	@go install github.com/golang/mock/[email protected]
 	@mockgen -source=x/logic/types/expected_keepers.go -package testutil -destination x/logic/testutil/expected_keepers_mocks.go
+	@mockgen -source=x/logic/fs/fs.go -package testutil -destination x/logic/testutil/fs_mocks.go
 
 ## Release:
 .PHONY: release-assets

app/app.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/fs"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -1017,7 +1016,7 @@ func (app *App) SimulationManager() *module.SimulationManager {
 
 // provideFS is used to provide the virtual file system used for the logic module
 // to load external file.
-func (app *App) provideFS(ctx context.Context) fs.FS {
+func (app *App) provideFS(ctx context.Context) logicfs.FS {
 	wasmHandler := logicfs.NewWasmHandler(app.WasmKeeper)
 	return logicfs.NewVirtualFS(ctx, []logicfs.URIHandler{wasmHandler})
 }

x/logic/fs/fs.go

@@ -5,14 +5,18 @@ import (
 	"io/fs"
 )
 
+type FS interface {
+	fs.FS
+}
+
 // VirtualFS is the custom virtual file system used into the blockchain.
 // It will hold a list of handler that can resolve file URI and return the corresponding binary file.
 type VirtualFS struct {
 	ctx    goctx.Context
 	router Router
 }
 
-var _ fs.FS = (*VirtualFS)(nil)
+var _ FS = (*VirtualFS)(nil)
 
 // NewVirtualFS return a new VirtualFS object that will handle all virtual file on the interpreter.
 // File can be provided from different sources like CosmWasm cw-storage smart contract.

x/logic/interpreter/registry.go

@@ -118,6 +118,7 @@ var Registry = map[string]RegistryEntry{
 	"sha_hash/2":                {predicate.SHAHash, 1},
 	"hex_bytes/2":               {predicate.HexBytes, 1},
 	"bech32_address/2":          {predicate.Bech32Address, 1},
+	"source_file/1":             {predicate.SourceFile, 1},
 }
 
 // RegistryNames is the list of the predicate names in the Registry.

x/logic/keeper/keeper.go

@@ -3,12 +3,12 @@ package keeper
 import (
 	goctx "context"
 	"fmt"
-	"io/fs"
 
 	"github.com/cosmos/cosmos-sdk/codec"
 	storetypes "github.com/cosmos/cosmos-sdk/store/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	paramtypes "github.com/cosmos/cosmos-sdk/x/params/types"
+	"github.com/okp4/okp4d/x/logic/fs"
 	"github.com/okp4/okp4d/x/logic/types"
 	"github.com/tendermint/tendermint/libs/log"
 )

x/logic/predicate/file.go

@@ -0,0 +1,93 @@
+package predicate
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"sort"
+
+	"github.com/ichiban/prolog/engine"
+)
+
+// SourceFile is a predicate that unify the given term with the currently loaded source file. The signature is as follows:
+//
+// source_file(?File).
+//
+// Where File represents a loaded source file.
+//
+// Example:
+//
+//	# Query all the loaded source files, in alphanumeric order.
+//	- source_file(File).
+//
+//	# Query the given source file is loaded.
+//	- source_file('foo.pl').
+func SourceFile(vm *engine.VM, file engine.Term, cont engine.Cont, env *engine.Env) *engine.Promise {
+	loaded := getLoadedSources(vm)
+
+	inputFile, err := getFile(env, file)
+	if err != nil {
+		return engine.Error(fmt.Errorf("source_file/1: %w", err))
+	}
+
+	if inputFile != nil {
+		if _, ok := loaded[*inputFile]; ok {
+			return engine.Unify(vm, file, engine.NewAtom(*inputFile), cont, env)
+		}
+		return engine.Delay()
+	}
+
+	promises := make([]func(ctx context.Context) *engine.Promise, 0, len(loaded))
+	sortedSource := sortLoadedSources(loaded)
+	for i := range sortedSource {
+		term := engine.NewAtom(sortedSource[i])
+		promises = append(
+			promises,
+			func(ctx context.Context) *engine.Promise {
+				return engine.Unify(
+					vm,
+					file,
+					term,
+					cont,
+					env,
+				)
+			})
+	}
+
+	return engine.Delay(promises...)
+}
+
+func getLoadedSources(vm *engine.VM) map[string]struct{} {
+	loadedField := reflect.ValueOf(vm).Elem().FieldByName("loaded").MapKeys()
+	loaded := make(map[string]struct{}, len(loadedField))
+	for _, value := range loadedField {
+		loaded[value.String()] = struct{}{}
+	}
+
+	return loaded
+}
+
+func sortLoadedSources(sources map[string]struct{}) []string {
+	result := make([]string, 0, len(sources))
+	for filename := range sources {
+		result = append(result, filename)
+	}
+	sort.SliceStable(result, func(i, j int) bool {
+		return result[i] < result[j]
+	})
+
+	return result
+}
+
+//nolint:nilnil
+func getFile(env *engine.Env, term engine.Term) (*string, error) {
+	switch file := env.Resolve(term).(type) {
+	case engine.Variable:
+	case engine.Atom:
+		strFile := file.String()
+		return &strFile, nil
+	default:
+		return nil, fmt.Errorf("cannot unify file with %T", term)
+	}
+	return nil, nil
+}

x/logic/predicate/file_test.go

@@ -0,0 +1,138 @@
+//nolint:gocognit
+package predicate
+
+import (
+	"fmt"
+	"net/url"
+	"testing"
+	"time"
+
+	"github.com/cosmos/cosmos-sdk/store"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/golang/mock/gomock"
+	"github.com/ichiban/prolog/engine"
+	"github.com/okp4/okp4d/x/logic/fs"
+	"github.com/okp4/okp4d/x/logic/testutil"
+	"github.com/okp4/okp4d/x/logic/types"
+	. "github.com/smartystreets/goconvey/convey"
+	"github.com/tendermint/tendermint/libs/log"
+	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
+	tmdb "github.com/tendermint/tm-db"
+)
+
+func TestSourceFile(t *testing.T) {
+	Convey("Given test cases", t, func() {
+		ctrl := gomock.NewController(t)
+		defer ctrl.Finish()
+
+		cases := []struct {
+			query       string
+			wantResult  []types.TermResults
+			wantError   error
+			wantSuccess bool
+		}{
+			{
+				query:       "source_file(file).",
+				wantSuccess: false,
+			},
+			{
+				query:       "consult(file1), consult(file2), source_file(file1).",
+				wantResult:  []types.TermResults{{}},
+				wantSuccess: true,
+			},
+			{
+				query:       "consult(file1), consult(file2), consult(file3), source_file(file2).",
+				wantResult:  []types.TermResults{{}},
+				wantSuccess: true,
+			},
+			{
+				query:       "consult(file1), consult(file2), source_file(file3).",
+				wantSuccess: false,
+			},
+			{
+				query:       "source_file(X).",
+				wantSuccess: false,
+			},
+			{
+				query:       "consult(file1), consult(file2), source_file(X).",
+				wantResult:  []types.TermResults{{"X": "file1"}, {"X": "file2"}},
+				wantSuccess: true,
+			},
+			{
+				query:       "consult(file2), consult(file3), consult(file1), source_file(X).",
+				wantResult:  []types.TermResults{{"X": "file1"}, {"X": "file2"}, {"X": "file3"}},
+				wantSuccess: true,
+			},
+			{
+				query:      "source_file(foo(bar)).",
+				wantResult: []types.TermResults{},
+				wantError:  fmt.Errorf("source_file/1: cannot unify file with *engine.compound"),
+			},
+		}
+
+		for nc, tc := range cases {
+			Convey(fmt.Sprintf("Given the query #%d: %s", nc, tc.query), func() {
+				Convey("and a mocked file system", func() {
+					uri, _ := url.Parse("file://dump.pl")
+					mockedFS := testutil.NewMockFS(ctrl)
+					mockedFS.EXPECT().Open(gomock.Any()).AnyTimes().Return(fs.NewVirtualFile(
+						[]byte("dumb(dumber)."),
+						uri,
+						time.Now(),
+					), nil)
+
+					Convey("and a context", func() {
+						db := tmdb.NewMemDB()
+						stateStore := store.NewCommitMultiStore(db)
+						ctx := sdk.NewContext(stateStore, tmproto.Header{}, false, log.NewNopLogger())
+
+						Convey("and a vm", func() {
+							interpreter := testutil.NewInterpreterMust(ctx)
+							interpreter.FS = mockedFS
+							interpreter.Register1(engine.NewAtom("source_file"), SourceFile)
+
+							Convey("When the predicate is called", func() {
+								sols, err := interpreter.QueryContext(ctx, tc.query)
+
+								Convey("Then the error should be nil", func() {
+									So(err, ShouldBeNil)
+									So(sols, ShouldNotBeNil)
+
+									Convey("and the bindings should be as expected", func() {
+										var got []types.TermResults
+										for sols.Next() {
+											m := types.TermResults{}
+											err := sols.Scan(m)
+											So(err, ShouldBeNil)
+
+											got = append(got, m)
+										}
+
+										if tc.wantError != nil {
+											So(sols.Err(), ShouldNotBeNil)
+											So(sols.Err().Error(), ShouldEqual, tc.wantError.Error())
+										} else {
+											So(sols.Err(), ShouldBeNil)
+
+											if tc.wantSuccess {
+												So(len(got), ShouldBeGreaterThan, 0)
+												So(len(got), ShouldEqual, len(tc.wantResult))
+												for iGot, resultGot := range got {
+													for varGot, termGot := range resultGot {
+														So(testutil.ReindexUnknownVariables(termGot), ShouldEqual, tc.wantResult[iGot][varGot])
+													}
+												}
+											} else {
+												So(len(got), ShouldEqual, 0)
+											}
+										}
+									})
+								})
+							})
+						})
+					})
+				})
+			})
+		}
+	})
+}

x/logic/testutil/logic.go

@@ -16,6 +16,7 @@ func NewInterpreterMust(ctx context.Context) (interpreter *prolog.Interpreter) {
 	interpreter.Register3(engine.NewAtom("op"), engine.Op)
 	interpreter.Register3(engine.NewAtom("compare"), engine.Compare)
 	interpreter.Register2(engine.NewAtom("="), engine.Unify)
+	interpreter.Register1(engine.NewAtom("consult"), engine.Consult)
 
 	err := interpreter.Compile(ctx, `
 						:-(op(1200, xfx, ':-')).