github.com/jackc/pgx/v5 v5.10.0: Identifier

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify github.com/jackc/pgx/v5.Identifier in pkg:golang/github.com/jackc/pgx/v5@v5.10.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/jackc/pgx/v5@v5.10.0
Demonstrate these symbols/APIs:
  - github.com/jackc/pgx/v5.Identifier
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@11.8.0
  - runtime: node@24.13.1

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:78d4bcc4c16ad18ee0e3ac8d099b99d5d3278cae8f4c10c6a0edc58770311db9","contract":["pgx.Identifier sanitizes and quotes single identifier","pgx.Identifier sanitizes and quotes multi-part schema qualified identifiers","pgx.Identifier escapes embedded double quotes by doubling them","pgx.Identifier returns empty string for empty identifier slice","sample helpers build qualified identifiers and sanitized SQL queries"],"goal":"verify github.com/jackc/pgx/v5.Identifier in pkg:golang/github.com/jackc/pgx/v5@v5.10.0","kind":"HOW","packages":["pkg:golang/github.com/jackc/pgx/v5@v5.10.0"],"schemaVersion":1,"symbols":["github.com/jackc/pgx/v5.Identifier"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","ecosystem":"golang","os":"windows","osVersionBucket":"11","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/jackc/pgx/v5@v5.10.0"],"schemaVersion":1,"symbols":["github.com/jackc/pgx/v5.Identifier"],"verifierAdapter":"golang@1"}

module sample

go 1.26.5

require (
	github.com/jackc/pgpassfile v1.0.0 // indirect
	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
	github.com/jackc/pgx/v5 v5.10.0 // indirect
	golang.org/x/text v0.29.0 // indirect
)

github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=
github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761/go.mod h1:5TJZWKEWniPve33vlWYSoGYefn3gLQRzjfDlhSJ9ZKM=
github.com/jackc/pgx/v5 v5.10.0 h1:VhSvgU2jSli8o3AqIEOTJr7rZwAEUVo4E4XhR94Zfr0=
github.com/jackc/pgx/v5 v5.10.0/go.mod h1:mal1tBGAFfLHvZzaYh77YS/eC6IX9OWbRV1QIIM0Jn4=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package sample

import (
	"fmt"
	"strings"

	"github.com/jackc/pgx/v5"
)

// QualifyTable constructs a pgx.Identifier for a table with an optional schema.
// If schema is empty, only the table name is included.
func QualifyTable(schema, table string) pgx.Identifier {
	if schema == "" {
		return pgx.Identifier{table}
	}
	return pgx.Identifier{schema, table}
}

// QualifyColumn constructs a pgx.Identifier for a column with schema and table qualifications.
// If schema is empty, only table and column are included.
func QualifyColumn(schema, table, column string) pgx.Identifier {
	if schema == "" {
		return pgx.Identifier{table, column}
	}
	return pgx.Identifier{schema, table, column}
}

// SanitizeTable returns the properly quoted and escaped SQL representation of a table identifier.
func SanitizeTable(schema, table string) string {
	return QualifyTable(schema, table).Sanitize()
}

// BuildSelectSQL constructs a basic SELECT statement with sanitized table and column identifiers.
func BuildSelectSQL(table pgx.Identifier, columns ...string) (string, error) {
	if len(table) == 0 {
		return "", fmt.Errorf("table identifier cannot be empty")
	}
	if len(columns) == 0 {
		return "", fmt.Errorf("at least one column must be specified")
	}

	sanitizedCols := make([]string, len(columns))
	for i, col := range columns {
		sanitizedCols[i] = pgx.Identifier{col}.Sanitize()
	}

	return fmt.Sprintf("SELECT %s FROM %s", strings.Join(sanitizedCols, ", "), table.Sanitize()), nil
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/jackc/pgx/v5.Identifier in pkg:golang/github.com/jackc/pgx/v5@v5.10.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/jackc/pgx/v5@v5.10.0"
  ],
  "symbols": [
    "github.com/jackc/pgx/v5.Identifier"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@11.8.0",
    "runtime": "node@24.13.1"
  }
}

package main

import (
	"fmt"
	"os"

	"github.com/jackc/pgx/v5"
	"sample"
)

func main() {
	// 1. Verify single identifier sanitization quotes identifier
	single := pgx.Identifier{"users"}
	if got, want := single.Sanitize(), `"users"`; got != want {
		fmt.Fprintf(os.Stderr, "single.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 2. Verify schema-qualified multi-part identifier quotes each part and joins with dot
	multi := pgx.Identifier{"public", "users"}
	if got, want := multi.Sanitize(), `"public"."users"`; got != want {
		fmt.Fprintf(os.Stderr, "multi.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 3. Verify three-part identifier (schema, table, column) sanitization
	threePart := pgx.Identifier{"analytics", "events", "user_id"}
	if got, want := threePart.Sanitize(), `"analytics"."events"."user_id"`; got != want {
		fmt.Fprintf(os.Stderr, "threePart.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 4. Verify embedded double quotes are escaped by doubling them
	quotes := pgx.Identifier{`my_"schema"`, `tab"le`}
	if got, want := quotes.Sanitize(), `"my_""schema"""."tab""le"`; got != want {
		fmt.Fprintf(os.Stderr, "quotes.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 5. Verify empty identifier slice produces empty string
	empty := pgx.Identifier{}
	if got, want := empty.Sanitize(), ""; got != want {
		fmt.Fprintf(os.Stderr, "empty.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 6. Verify sample.QualifyTable and sample.SanitizeTable helpers
	tableIdentNoSchema := sample.QualifyTable("", "orders")
	if got, want := tableIdentNoSchema.Sanitize(), `"orders"`; got != want {
		fmt.Fprintf(os.Stderr, "tableIdentNoSchema.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	tableIdentWithSchema := sample.QualifyTable("sales", "orders")
	if got, want := tableIdentWithSchema.Sanitize(), `"sales"."orders"`; got != want {
		fmt.Fprintf(os.Stderr, "tableIdentWithSchema.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	if got, want := sample.SanitizeTable("sales", "orders"), `"sales"."orders"`; got != want {
		fmt.Fprintf(os.Stderr, "SanitizeTable mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 7. Verify sample.QualifyColumn helper
	colIdent := sample.QualifyColumn("sales", "orders", "total_amount")
	if got, want := colIdent.Sanitize(), `"sales"."orders"."total_amount"`; got != want {
		fmt.Fprintf(os.Stderr, "colIdent.Sanitize() mismatch: got %q, want %q\n", got, want)
		os.Exit(1)
	}

	// 8. Verify sample.BuildSelectSQL produces formatted SQL query with sanitized identifiers
	query, err := sample.BuildSelectSQL(pgx.Identifier{"public", "users"}, "id", "user_name", `weird"col`)
	if err != nil {
		fmt.Fprintf(os.Stderr, "BuildSelectSQL failed: %v\n", err)
		os.Exit(1)
	}
	expectedQuery := `SELECT "id", "user_name", "weird""col" FROM "public"."users"`
	if query != expectedQuery {
		fmt.Fprintf(os.Stderr, "BuildSelectSQL output mismatch: got %q, want %q\n", query, expectedQuery)
		os.Exit(1)
	}

	// 9. Verify error cases for BuildSelectSQL
	if _, err := sample.BuildSelectSQL(pgx.Identifier{}, "id"); err == nil {
		fmt.Fprintf(os.Stderr, "expected error when table identifier is empty, got nil\n")
		os.Exit(1)
	}
	if _, err := sample.BuildSelectSQL(pgx.Identifier{"users"}); err == nil {
		fmt.Fprintf(os.Stderr, "expected error when no columns provided, got nil\n")
		os.Exit(1)
	}

	fmt.Println("All pgx.Identifier contract assertions passed.")
}