Crate jscpd_rs 

Native Rust API for jscpd-rs, a 50x+ faster duplicate-code detector for local development and CI/CD.

jscpd-rs scans a codebase, finds copy-paste fragments across files, writes console, JSON, SARIF, HTML, XML, CSV, Markdown, badge, and Xcode reports, and can fail a build when duplication crosses a configured threshold.

It is a native Rust implementation of the common jscpd command-line workflow: upstream-style CLI flags, .jscpd.json and package.json#jscpd configuration, report formats, exit-code behavior, Git blame, and server snippet checks. The current public benchmark suite records 50x+ speedups on pinned React, Next.js, and Prometheus cases while using a coverage-first compatibility gate against upstream jscpd.

This crate exposes the same detector core used by the jscpd and jscpd-server binaries: option parsing, file discovery, tokenization, duplicate detection, statistics, and in-memory source checks.

Quick Start

Scan paths using the same option model as the CLI:

use std::path::PathBuf;

let mut options = jscpd_rs::get_default_options();
options.paths = vec![PathBuf::from("src")];
options.reporters.clear();
options.silent = true;

let result = jscpd_rs::detect_clones_and_statistics(&options)?;
println!("{} clones", result.clones.len());

Check prepared in-memory sources without touching the filesystem:

let mut options = jscpd_rs::get_default_options();
options.reporters.clear();
options.min_lines = 2;
options.min_tokens = 5;

let files = vec![
    jscpd_rs::SourceFile {
        source_id: "a.js".to_string(),
        format: "javascript".to_string(),
        content: "const a = 1;\nconst b = 2;\nconst c = a + b;\n".to_string(),
    },
    jscpd_rs::SourceFile {
        source_id: "b.js".to_string(),
        format: "javascript".to_string(),
        content: "const a = 1;\nconst b = 2;\nconst c = a + b;\n".to_string(),
    },
];

let result = jscpd_rs::detect_source_files(files, &options);
assert!(!result.clones.is_empty());

Main Entry Points

• get_options_from_args parses upstream-style CLI arguments into Options.
• detect_clones and detect_clones_and_statistics run discovery, tokenization, duplicate detection, statistics, and optional Git blame.
• detect_source_files runs detection against caller-provided SourceFile values and is the best entry point for editors, servers, and tests.
• Tokenizer exposes the native token map generator used by the detector.
• Detector and MemoryStore provide Rust counterparts for the main upstream core classes.
• jscpd and jscpd_with_exit_callback provide an embeddable argv runner similar to upstream jscpd(argv, exitCallback?).

Compatibility Model

The release gate is coverage-first: for the same inputs and options, this crate must not miss duplicated source lines reported by upstream jscpd. Extra Rust findings remain visible in compatibility reports while the implementation converges on exact parity.

The first release intentionally keeps the detector native-only. Dynamic npm reporters, stores, listeners, and plugins are not loaded by this crate.

See the README and User Guide for CLI, configuration, reporter, server, and CI examples.

Modules

server

Structs

BlamedLine

Git blame information for one duplicated source line.

Cli

CloneMatch

Pair of duplicated fragments reported as one clone.

DetectionResult

Complete detector output.

DetectionToken

Detection token after mode filtering and jscpd-compatible hashing.

Detector

Incremental detector facade for native integrations.

FormatMappings

Additional format mappings from extensions or exact filenames to formats.

Fragment

One duplicated fragment in a source file.

JscpdOutcome

Location

One-based source location used in tokens, fragments, and reports.

MemoryStore

MemoryStoreError

Options

Normalized detector options shared by the CLI, server, and Rust API.

SkippedClone

Clone skipped from final output with compatibility/debug messages.

SourceFile

Source content prepared by the caller for in-memory detection.

SourceSummary

Summary of one analyzed source.

SourceTokenMap

Token map associated with a source identifier and line count.

Statistic

StatisticRow

Aggregated duplication counters for a source, format, or whole run.

Statistics

Duplication statistics for a full detection run.

ThresholdExceeded

TokenMap

Token map for a single detected format block.

Tokenizer

Native tokenizer used by the detector.

Enums

ExitCode

Mode

Functions

detect_clones

Detect clones from files discovered through Options::paths.

detect_clones_and_statistic

Upstream-named alias for detect_clones_and_statistics.

detect_clones_and_statistics

Detect clones and return both clone matches and aggregate statistics.

detect_source_files

Detect clones in prepared in-memory sources.

get_default_options

Return the upstream-compatible default option set.

get_format_by_file

Resolve a source format from a path using the built-in extension and filename registry.

get_format_by_file_with_mappings

Resolve a source format from a path with caller-provided extension and filename mappings.

get_options_from_args

Parse upstream-style command-line arguments into normalized Options.

get_supported_formats

Return the names of all formats known to the synchronized format registry.

jscpd

jscpd_with_exit_callback

run_cli_args

run_current_process

upstream_stdout_error

Type Aliases

BlamedLines

Git blame lines keyed by line number.