Add columns exporter to referencer (#9)

.github/workflows/cloc.yml

@@ -18,7 +18,7 @@ jobs:
       - name: Count Lines Of Code
         id: loc
         run: |
-          curl -OL https://github.com/vearutop/builds/releases/download/sccdiff-v0/sccdiff && chmod +x sccdiff
+          curl -OL https://github.com/vearutop/sccdiff/releases/download/v1.0.1/linux_amd64.tar.gz && tar xf linux_amd64.tar.gz
           OUTPUT=$(cd pr && ../sccdiff -basedir ../base)
           OUTPUT="${OUTPUT//'%'/'%25'}"
           OUTPUT="${OUTPUT//$'\n'/'%0A'}"

.github/workflows/golangci-lint.yml

@@ -18,7 +18,7 @@ jobs:
         uses: golangci/golangci-lint-action@v2.5.2
         with:
           # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
-          version: v1.39.0
+          version: v1.40.1
 
           # Optional: working directory, useful for monorepos
           # working-directory: somedir

.golangci.yml

@@ -32,6 +32,7 @@ linters:
     - forcetypeassert
     - scopelint # deprecated
     - ifshort # too many false positives
+    - golint # deprecated
 
 issues:
   exclude-use-default: false

Makefile

@@ -1,4 +1,4 @@
-#GOLANGCI_LINT_VERSION := "v1.39.0" # Optional configuration to pinpoint golangci-lint version.
+#GOLANGCI_LINT_VERSION := "v1.40.1" # Optional configuration to pinpoint golangci-lint version.
 
 # The head of Makefile determines location of dev-go to include standard targets.
 GO ?= go

go.mod

@@ -5,8 +5,8 @@ go 1.13
 require (
 	github.com/DATA-DOG/go-sqlmock v1.5.0
 	github.com/Masterminds/squirrel v1.5.0
-	github.com/bool64/ctxd v0.1.5
-	github.com/bool64/dev v0.1.32
+	github.com/bool64/ctxd v1.0.0
+	github.com/bool64/dev v0.1.35
 	github.com/jmoiron/sqlx v1.3.4
 	github.com/stretchr/testify v1.6.1
 )

go.sum

@@ -2,12 +2,12 @@ github.com/DATA-DOG/go-sqlmock v1.5.0 h1:Shsta01QNfFxHCfpW6YH2STWB0MudeXXEWMr20O
 github.com/DATA-DOG/go-sqlmock v1.5.0/go.mod h1:f/Ixk793poVmq4qj/V1dPUg2JEAKC73Q5eFN3EC/SaM=
 github.com/Masterminds/squirrel v1.5.0 h1:JukIZisrUXadA9pl3rMkjhiamxiB0cXiu+HGp/Y8cY8=
 github.com/Masterminds/squirrel v1.5.0/go.mod h1:NNaOrjSoIDfDA40n7sr2tPNZRfjzjA400rg+riTZj10=
-github.com/bool64/ctxd v0.1.5 h1:ilZo2AgQ+NG9NyusoYEdcMcGgleAFDnrju+5KMxwUbk=
-github.com/bool64/ctxd v0.1.5/go.mod h1:+rjDVFNOJeO+xlvMqQfG0p53CzuRB7FhPSo5nWSkpQ0=
+github.com/bool64/ctxd v1.0.0 h1:Btvo6BU5FulG7H2V9m5Il/2vcqT0nxe86AiEpbG08/I=
+github.com/bool64/ctxd v1.0.0/go.mod h1:+rjDVFNOJeO+xlvMqQfG0p53CzuRB7FhPSo5nWSkpQ0=
 github.com/bool64/dev v0.1.25/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
 github.com/bool64/dev v0.1.28/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
-github.com/bool64/dev v0.1.32 h1:/9dpNGF/73diJzQxZS2hOxOPrsbTyLhr0VrQztylSKY=
-github.com/bool64/dev v0.1.32/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
+github.com/bool64/dev v0.1.35 h1:uouBAq2kAJ+k9UypYRs118bAYttNQWDyK4IzjfLb5fc=
+github.com/bool64/dev v0.1.35/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

mapper.go

@@ -10,9 +10,9 @@ import (
 )
 
 var (
-	errFieldNotFound = errors.New("could not find field value in struct")
-	errNotAPointer   = errors.New("can not take address of structure, please pass a pointer")
-	errNilArgument   = errors.New("structPtr and fieldPtr are required")
+	errUnknownFieldOrRow = errors.New("unknown field or row or not a pointer")
+	errNotAPointer       = errors.New("can not take address of structure, please pass a pointer")
+	errNilArgument       = errors.New("structPtr and fieldPtr are required")
 )
 
 // Mapper prepares select, insert and update statements.
@@ -354,7 +354,7 @@ func (sm *Mapper) FindColumnName(structPtr, fieldPtr interface{}) (string, error
 		}
 	}
 
-	return "", errFieldNotFound
+	return "", errUnknownFieldOrRow
 }
 
 func (sm *Mapper) typeMap(t reflect.Type) *reflectx.StructMap {
@@ -424,6 +424,10 @@ func (sm *Mapper) FindColumnNames(structPtr interface{}) (map[interface{}]string
 
 	tm := sm.typeMap(t)
 	for _, fi := range tm.Index {
+		if fi.Embedded {
+			continue
+		}
+
 		fv := reflectx.FieldByIndexesReadOnly(v, fi.Index)
 		res[fv.Addr().Interface()] = fi.Name
 	}

mapper_test.go

@@ -529,7 +529,7 @@ func TestMapper_FindColumnName(t *testing.T) {
 		{&s, &s.B, "b", ""},
 		{&s, &s.C, "c", ""},
 		{nil, nil, "", "structPtr and fieldPtr are required"},
-		{&s, 123, "", "could not find field value in struct"},
+		{&s, 123, "", "unknown field or row or not a pointer"},
 		{s, &s.A, "", "can not take address of structure, please pass a pointer"},
 	} {
 		tc := tc

referencer.go

@@ -2,6 +2,7 @@ package sqluct
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 )
 
@@ -58,7 +59,8 @@ type Referencer struct {
 	// Default QuoteNoop.
 	IdentifierQuoter func(tableAndColumn ...string) string
 
-	refs map[interface{}]string
+	refs    map[interface{}]string
+	columns map[interface{}][]string
 }
 
 // ColumnsOf makes a Mapper option to prefix columns with table alias.
@@ -95,10 +97,32 @@ func (r *Referencer) AddTableAlias(rowStructPtr interface{}, alias string) {
 		r.refs = make(map[interface{}]string, len(f)+1)
 	}
 
+	if r.columns == nil {
+		r.columns = make(map[interface{}][]string)
+	}
+
 	if alias != "" {
 		r.refs[rowStructPtr] = r.Q(alias)
 	}
 
+	columns := make([]string, 0, len(f))
+
+	for _, fieldName := range f {
+		var col string
+
+		if alias == "" {
+			col = r.Q(fieldName)
+		} else {
+			col = r.Q(alias, fieldName)
+		}
+
+		columns = append(columns, col)
+	}
+
+	sort.Strings(columns)
+
+	r.columns[rowStructPtr] = columns
+
 	for ptr, fieldName := range f {
 		if alias == "" {
 			r.refs[ptr] = r.Q(fieldName)
@@ -125,7 +149,7 @@ func (r *Referencer) Ref(ptr interface{}) string {
 		return ref
 	}
 
-	panic(errFieldNotFound)
+	panic(errUnknownFieldOrRow)
 }
 
 // Fmt formats according to a format specified replacing ptrs with their reference strings where possible.
@@ -144,3 +168,12 @@ func (r *Referencer) Fmt(format string, ptrs ...interface{}) string {
 
 	return fmt.Sprintf(format, args...)
 }
+
+// Cols returns column references of a row structure.
+func (r *Referencer) Cols(ptr interface{}) []string {
+	if cols, found := r.columns[ptr]; found {
+		return cols
+	}
+
+	panic(errUnknownFieldOrRow)
+}

referencer_test.go

@@ -89,6 +89,30 @@ func TestReferencer_Ref(t *testing.T) {
 	})
 }
 
+func TestReferencer_Cols(t *testing.T) {
+	rf := sqluct.Referencer{}
+	rf.IdentifierQuoter = sqluct.QuoteBackticks
+
+	type r struct {
+		ID   int    `db:"id,omitempty"`
+		Name string `db:"name"`
+	}
+
+	row := &r{}
+	row2 := &r{}
+	unknown := &r{}
+
+	rf.AddTableAlias(row, "some_table")
+	rf.AddTableAlias(row2, "")
+
+	assert.Equal(t, []string{"`some_table`.`id`", "`some_table`.`name`"}, rf.Cols(row))
+	assert.Equal(t, []string{"`id`", "`name`"}, rf.Cols(row2))
+
+	assert.Panics(t, func() {
+		rf.Cols(unknown)
+	})
+}
+
 func TestQuoteNoop(t *testing.T) {
 	assert.Equal(t, "one.two", sqluct.QuoteNoop("one", "two"))
 	assert.Equal(t, "", sqluct.QuoteNoop())