file-compare
Compare two small text files by line without editing either.
newpanecommand
Compare two small text files by line without editing either.
Compare two small text files by line without editing either.
Use it when: Check config or fixture differences.
Screenshot of this mod's render tree in the fixture preview, with sample data. This is not a capture of the Claude Code application. How previews are made.
claude plugin marketplace add whyashthakker/awesome-claude-code-mods
claude plugin install file-compare@awesome-claude-code-modsRun /reload-plugins in an existing session, then /file-compare. Use Tab and Enter to operate controls; Esc closes the pane. Terminal and Desktop Code tab supported; pane UI is unavailable in claude -p and the VS Code chat panel.
Try the source without installing:
claude --plugin-dir ./mods/file-compareReads two explicitly chosen text files up to 64 KiB each. Positional comparison, not an edit-distance diff.
Module variables reset on hot reload. All display output is bounded; viewers may truncate long content to 9,000 characters. Relative file paths and Git commands use the session working directory.
Tested with Claude Code 2.1.288. Minimum documented mods version: 2.1.287. The API can change; validate against your installed version.
claude plugin validate mods/file-compare --strict
claude plugin test mods/file-compareTests cover plugin commands, pane isolation, both UI surfaces, and the behavior described in tests/register.test.ts. Drawing tests validate element trees; they do not verify pixels painted by the native apps. Validation details.
MIT licensed. No runtime packages or build step required.
hooks/register.js 48 lines1import { clean, text, code, row, frame, bar, pretty, bounded, entries, safePath } from './ui.js'
2const ID = "file-compare"
3let left='before.txt',right='after.txt',report=''
4
5async function load($) {
6 try {
7 const a=await $.fs.stat(safePath(left)),b=await $.fs.stat(safePath(right))
8 if(a.size>65536||b.size>65536)throw new Error('Each file must be at most 64 KiB.')
9 const x=(await $.fs.read(left)).split('\n'),y=(await $.fs.read(right)).split('\n')
10 const diff=[]
11 for(let i=0;i<Math.max(x.length,y.length);i++) if(x[i]!==y[i])diff.push((i+1)+': - '+(x[i]??'[missing]')+'\n + '+(y[i]??'[missing]'))
12 report=diff.length?diff.length+' differing line positions (positional comparison)\n\n'+diff.slice(0,100).join('\n'):'Files are identical.'
13 } catch(error){report=error.message}
14 $.ui.invalidate('ui.render')
15}
16
17export function register(on) {
18 on('session.start', async ($, e, next) => {
19
20 await $.command.register({name:ID, description:"Compare two small text files by line without editing either.", immediate:true, argumentHint:"[path]"})
21 return next(e)
22 })
23 on('command.run', {command:"file-compare"}, async ($, e) => {
24 await load($)
25 await $.ui.open({id:ID,title:"File Compare",focus:true,closeOnEscape:true})
26 return {}
27 })
28
29 on('ui.render', {component:'Pane'}, async ($, e, next) => {
30 if(e.requestId !== ID) return next(e)
31 const E = $.ui.resolve(e)
32 try {
33 const body = await draw($, E)
34 return frame(E,"File Compare","Compare two small text files by line without editing either.",body)
35 } catch(error) {
36 return frame(E,"File Compare",'Unable to inspect this data.',[text(E,error.message,{color:'yellow'}),E.Button({key:'refresh',label:'Refresh',onPress:()=>$.ui.invalidate('ui.render')})])
37 }
38 })
39}
40async function draw($, E) {
41 const refresh = E.Button({key:'refresh',label:'Refresh',hotkey:'r',plain:true,onPress:()=>$.ui.invalidate('ui.render')})
42
43return [E.Input({key:'left',label:'Left file',value:left,submitLabel:'set',onSubmit:async(v)=>{left=v;await load($)}}),
44 E.Input({key:'right',label:'Right file',value:right,submitLabel:'compare',onSubmit:async(v)=>{right=v;await load($)}}),
45 code(E,report),E.Button({key:'refresh',label:'Compare again',onPress:()=>load($)})]
46
47}
48hooks/ui.js 36 lines1// Pure UI helpers. No engine access; each plugin contains its own copy.
2export function clean(value, limit = 9000) {
3 return String(value ?? '').replace(/[\u0000-\u0008\u000b\u000c\u000e-\u001f\u007f-\u009f]/g, '').slice(0, limit)
4}
5export function text(E, value, props = {}) {
6 return E.Text({ ...props, children: [clean(value)] })
7}
8export function code(E, value, language = 'text') {
9 return E.Code({ source: clean(value), language })
10}
11export function row(E, children) {
12 return E.Box({ flexDirection: 'row', columnGap: 2, flexWrap: 'wrap', children })
13}
14export function frame(E, title, subtitle, children) {
15 return E.Box({ flexDirection: 'column', gap: 1, children: [
16 text(E, title, { bold: true, color: 'cyan' }),
17 text(E, subtitle, { dimColor: true }), ...children,
18 ] })
19}
20export function bar(percent, width = 24) {
21 const p = Math.max(0, Math.min(100, Number(percent) || 0))
22 const n = Math.round(p / 100 * width)
23 return '[' + '#'.repeat(n) + '-'.repeat(width - n) + '] ' + p.toFixed(1) + '%'
24}
25export function pretty(value) { return JSON.stringify(value, null, 2) }
26export function bounded(value, max = 9000) {
27 if (value.length > max) throw new Error('Input exceeds ' + max + ' characters. Use a smaller selection.')
28 return value
29}
30export function entries(value) { return value && typeof value === 'object' ? Object.entries(value) : [] }
31export function safePath(value) {
32 const path = value.trim()
33 if (!path || path.startsWith('-') || /[\x00-\x1f]/.test(path)) throw new Error('Enter a path without control characters or leading flags.')
34 return path
35}
36