Implement diagnostic quota logic

packages/steiger/src/app.ts

@@ -8,12 +8,13 @@ import { $enabledRules, getEnabledRules, getGlobalIgnores, getPluginByRuleName }
 import { runRule } from './features/run-rule'
 import { removeGlobalIgnoreFromVfs } from './features/remove-global-ignores-from-vfs'
 import { calculateFinalSeverities } from './features/calculate-diagnostic-severities'
+import { collapseDiagnostics } from './features/collapse-diagnostics'
 
 async function runRules({ vfs, rules }: { vfs: Folder; rules: Array<Rule> }) {
   const vfsWithoutGlobalIgnores = removeGlobalIgnoreFromVfs(vfs, getGlobalIgnores())
 
   const ruleResults = await Promise.all(rules.map((rule) => runRule(vfsWithoutGlobalIgnores, rule)))
-  return ruleResults.flatMap((r, ruleResultsIndex) => {
+  const diagnosticsPerRule = ruleResults.map((r, ruleResultsIndex) => {
     const { diagnostics } = r
     if (diagnostics.length === 0) {
       return []
@@ -44,6 +45,9 @@ async function runRules({ vfs, rules }: { vfs: Folder; rules: Array<Rule> }) {
       return finalDiagnostic
     })
   })
+  const collapsedDiagnostics = collapseDiagnostics(diagnosticsPerRule)
+
+  return collapsedDiagnostics.flat()
 }
 
 export const linter = {

packages/steiger/src/features/collapse-diagnostics/diagnostic-quota.test.ts

@@ -0,0 +1,253 @@
+import { describe, expect, it } from 'vitest'
+import { trimDiagnosticsToMeetQuota } from './diagnostic-quota'
+
+const defaultLocation = {
+  path: '/users/user/file',
+}
+
+const defaultSeverity = 'error' as 'warn' | 'error'
+
+describe('trimDiagnosticsToMeetQuota', () => {
+  it('should return the same diagnostics if they are below the quota', () => {
+    const diagnosticPerRule = [
+      [
+        {
+          message: 'First rule, first message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, second message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, third message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Second rule, first message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'Second rule, second message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+    ]
+
+    const result = trimDiagnosticsToMeetQuota(diagnosticPerRule, 10)
+
+    expect(result).toEqual(diagnosticPerRule)
+  })
+
+  it('should return no diagnostics if the quota is 0', () => {
+    const diagnosticPerRule = [
+      [
+        {
+          message: 'First rule, first message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, second message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, third message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Second rule, first message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'Second rule, second message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+    ]
+
+    const result = trimDiagnosticsToMeetQuota(diagnosticPerRule, 0)
+
+    expect(result).toEqual([[], []])
+  })
+
+  it('should spread the quota evenly between rules', () => {
+    const diagnosticPerRule = [
+      [
+        {
+          message: 'First rule, first message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, second message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, third message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Second rule, first message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'Second rule, second message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+    ]
+
+    const result = trimDiagnosticsToMeetQuota(diagnosticPerRule, 2)
+
+    expect(result).toEqual([
+      [
+        {
+          message: 'First rule, first message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Second rule, first message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+    ])
+  })
+
+  it('should take first x rule diagnostics if the quota is less than the number of rules', () => {
+    const diagnosticPerRule = [
+      [
+        {
+          message: 'First rule, first message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, second message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'First rule, third message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Second rule, first message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'Second rule, second message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Third rule, first message',
+          ruleName: 'rule-3',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'Third rule, second message',
+          ruleName: 'rule-3',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Forth rule, first message',
+          ruleName: 'rule-4',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+        {
+          message: 'Forth rule, second message',
+          ruleName: 'rule-4',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+    ]
+
+    const result = trimDiagnosticsToMeetQuota(diagnosticPerRule, 3)
+
+    expect(result).toEqual([
+      [
+        {
+          message: 'First rule, first message',
+          ruleName: 'rule-1',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Second rule, first message',
+          ruleName: 'rule-2',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [
+        {
+          message: 'Third rule, first message',
+          ruleName: 'rule-3',
+          location: defaultLocation,
+          severity: defaultSeverity,
+        },
+      ],
+      [],
+    ])
+  })
+})

packages/steiger/src/features/collapse-diagnostics/diagnostic-quota.ts

@@ -0,0 +1,33 @@
+import { Diagnostic } from '@steiger/types'
+
+function distributeQuota(buckets: Array<number>, quota: number) {
+  // const allItems = buckets.reduce((acc, bucket) => acc + bucket, 0)
+  const quotaPerBucket = buckets.slice(0).fill(0)
+  let remainingQuota = quota
+
+  // Temporary algorithm to distribute the quota
+  for (let i = 0; remainingQuota > 0; i++) {
+    const bucket = buckets[i]
+
+    // If it went beyond the last bucket, start from the first one
+    if (bucket === undefined) {
+      i = -1
+      continue
+    }
+
+    // If the bucket does not contain any items, skip it
+    if (bucket !== 0) {
+      quotaPerBucket[i]++
+      remainingQuota--
+    }
+  }
+
+  return quotaPerBucket
+}
+
+export function trimDiagnosticsToMeetQuota(diagnosticsPerRule: Array<Array<Diagnostic>>, quota: number) {
+  const diagnosticCountPerRule = diagnosticsPerRule.map((diagnostics) => diagnostics.length)
+  const quotaPerRule = distributeQuota(diagnosticCountPerRule, quota)
+
+  return diagnosticsPerRule.map((diagnostics, i) => diagnostics.slice(0, quotaPerRule[i]))
+}

packages/steiger/src/features/collapse-diagnostics/index.ts

@@ -0,0 +1,7 @@
+import { trimDiagnosticsToMeetQuota } from './diagnostic-quota'
+import { Diagnostic } from '@steiger/types'
+
+const DEFAULT_QUOTA = 20
+
+export const collapseDiagnostics = (diagnosticPerRule: Array<Array<Diagnostic>>) =>
+  trimDiagnosticsToMeetQuota(diagnosticPerRule, DEFAULT_QUOTA)