Go error rules

README.md

@@ -54,14 +54,17 @@ $ semgrep --config /path/to/semgrep-rules/hanging-goroutine.yml -o leaks.txt'
 | [eth-rpc-tracetransaction](go/eth-rpc-tracetransaction.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.eth-rpc-tracetransaction.eth-rpc-tracetransaction) | 🟥 | 🌕 | Detects attempts to extract trace information from an EVM transaction or block. In exchange or bridge applications, extra logic must be implemented encapsulating these endpoints to prevent the values transferred during reverted call frames from being counted. |
 | [eth-txreceipt-status](go/eth-txreceipt-status.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.eth-txreceipt-status.eth-txreceipt-status) | 🟥 | 🌕 | Detects when a transaction receipt's status is read |
 | [hanging-goroutine](go/hanging-goroutine.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.hanging-goroutine.hanging-goroutine) | 🟩 | 🌗 | Goroutine leaks |
+| [http-error-missing-return](go/http-error-missing-return.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.http-error-missing-return.http-error-missing-return) | 🟧 | 🌗 | Missing `return` after `http.Error` lets the handler continue executing |
 | [invalid-usage-of-modified-variable](go/invalid-usage-of-modified-variable.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.invalid-usage-of-modified-variable.invalid-usage-of-modified-variable) | 🟧 | 🌘 | Possible unintentional assignment when an error occurs |
 | [iterate-over-empty-map](go/iterate-over-empty-map.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.iterate-over-empty-map.iterate-over-empty-map) | 🟩 | 🌗 | Probably redundant iteration over an empty map |
 | [missing-runlock-on-rwmutex](go/missing-runlock-on-rwmutex.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.missing-runlock-on-rwmutex.missing-runlock-on-rwmutex) | 🟧 | 🌗 | Missing `RUnlock` on an `RWMutex` lock before returning from a function |
 | [missing-unlock-before-return](go/missing-unlock-before-return.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.missing-unlock-before-return.missing-unlock-before-return) | 🟧 | 🌗 | Missing `mutex` unlock before returning from a function |
 | [nil-check-after-call](go/nil-check-after-call.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.nil-check-after-call.nil-check-after-call) | 🟧 | 🌗 | Possible nil dereferences |
+| [pkg-errors-wrap-nil-err](go/pkg-errors-wrap-nil-err.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.pkg-errors-wrap-nil-err.pkg-errors-wrap-nil-err) | 🟧 | 🌗 | `pkg/errors` wrap-family call on a provably-nil error — silently swallows the failure path |
 | [racy-append-to-slice](go/racy-append-to-slice.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.racy-append-to-slice.racy-append-to-slice) | 🟧 | 🌗 | Concurrent calls to `append` from multiple goroutines |
 | [racy-write-to-map](go/racy-write-to-map.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.racy-write-to-map.racy-write-to-map) | 🟧 | 🌗 | Concurrent writes to the same map in multiple goroutines |
 | [servercodec-readrequestbody-unhandled-nil](go/servercodec-readrequestbody-unhandled-nil.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.servercodec-readrequestbody-unhandled-nil.servercodec-readrequestbody-unhandled-nil) | 🟩 | 🌘 | Possible incorrect `ServerCodec` interface implementation |
+| [shadowed-err-check](go/shadowed-err-check.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.shadowed-err-check.shadowed-err-check) | 🟧 | 🌗 | Shadowed error variable: declared `err` is not the one checked against `nil` |
 | [string-to-int-signedness-cast](go/string-to-int-signedness-cast.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.string-to-int-signedness-cast.string-to-int-signedness-cast) | 🟧 | 🌘 | Integer underflows |
 | [sync-mutex-value-copied](go/sync-mutex-value-copied.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.sync-mutex-value-copied.sync-mutex-value-copied) | 🟩 | 🌘 | Copying of `sync.Mutex` via value receivers |
 | [unmarshal-tag-is-dash](go/unmarshal_tag_is_dash.yaml) | [🛝🔗](https://semgrep.dev/playground/r/trailofbits.go.unmarshal_tag_is_dash.unmarshal-tag-is-dash) | 🟧 | 🌘 |  |