enable govet shadow linter and fix issues

.golangci.yml

@@ -38,7 +38,12 @@ linters-settings:
     # We do this 121 times and never check the error.
     - (*github.com/spf13/cobra.Command).MarkFlagRequired
   govet:
+    check-shadowing: true
     settings:
+      shadow:
+        # explanation of strict vs non-strict:
+        # https://github.com/golang/tools/blob/v0.7.0/go/analysis/passes/shadow/shadow.go#L104-L122
+        strict: false
       printf:
         # Comma-separated list of print function names to check (in addition to default, see `go tool vet help printf`).
         # Default: []
@@ -118,6 +123,11 @@ issues:
         # - revive
         - staticcheck
         - typecheck
+    # allow shadowing in test code
+    - path: _test\.go
+      linters:
+        - govet
+      text: "shadows declaration at line"
     # Ignore missing parallel tests in existing packages
     - path: ^agreement.*_test\.go
       linters:

agreement/demux.go

@@ -125,9 +125,9 @@ func (d *demux) tokenizeMessages(ctx context.Context, net Network, tag protocol.
 				if err != nil {
 					warnMsg := fmt.Sprintf("disconnecting from peer: error decoding message tagged %v: %v", tag, err)
 					// check protocol version
-					cv, err := d.ledger.ConsensusVersion(d.ledger.NextRound())
-					if err == nil {
-						if _, ok := config.Consensus[cv]; !ok {
+					cv, cvErr := d.ledger.ConsensusVersion(d.ledger.NextRound())
+					if cvErr == nil {
+						if _, found := config.Consensus[cv]; !found {
 							warnMsg = fmt.Sprintf("received proposal message was ignored. The node binary doesn't support the next network consensus (%v) and would no longer be able to process agreement messages", cv)
 						}
 					}

agreement/pseudonode.go

@@ -295,17 +295,17 @@ func (n asyncPseudonode) makeProposals(round basics.Round, period period, accoun
 	votes := make([]unauthenticatedVote, 0, len(accounts))
 	proposals := make([]proposal, 0, len(accounts))
 	for _, acc := range accounts {
-		payload, proposal, err := proposalForBlock(acc.Account, acc.VRF, ve, period, n.ledger)
-		if err != nil {
-			n.log.Errorf("pseudonode.makeProposals: could not create proposal for block (address %v): %v", acc.Account, err)
+		payload, proposal, pErr := proposalForBlock(acc.Account, acc.VRF, ve, period, n.ledger)
+		if pErr != nil {
+			n.log.Errorf("pseudonode.makeProposals: could not create proposal for block (address %v): %v", acc.Account, pErr)
 			continue
 		}
 
 		// attempt to make the vote
 		rv := rawVote{Sender: acc.Account, Round: round, Period: period, Step: propose, Proposal: proposal}
-		uv, err := makeVote(rv, acc.VotingSigner(), acc.VRF, n.ledger)
-		if err != nil {
-			n.log.Warnf("pseudonode.makeProposals: could not create vote: %v", err)
+		uv, vErr := makeVote(rv, acc.VotingSigner(), acc.VRF, n.ledger)
+		if vErr != nil {
+			n.log.Warnf("pseudonode.makeProposals: could not create vote: %v", vErr)
 			continue
 		}
 

cmd/algocfg/profileCommand.go

@@ -142,13 +142,13 @@ var setProfileCmd = &cobra.Command{
 				reportErrorf("%v", err)
 			}
 			file := filepath.Join(dataDir, config.ConfigFilename)
-			if _, err := os.Stat(file); !forceUpdate && err == nil {
+			if _, statErr := os.Stat(file); !forceUpdate && statErr == nil {
 				fmt.Printf("A config.json file already exists for this data directory. Would you like to overwrite it? (Y/n)")
 				reader := bufio.NewReader(os.Stdin)
-				resp, err := reader.ReadString('\n')
+				resp, readErr := reader.ReadString('\n')
 				resp = strings.TrimSpace(resp)
-				if err != nil {
-					reportErrorf("Failed to read response: %v", err)
+				if readErr != nil {
+					reportErrorf("Failed to read response: %v", readErr)
 				}
 				if strings.ToLower(resp) == "n" {
 					reportInfof("Exiting without overwriting existing config.")

cmd/catchpointdump/net.go

@@ -314,8 +314,8 @@ func loadAndDump(addr string, tarFile string, genesisInitState ledgercore.InitSt
 	}
 
 	defer func() {
-		if err := deleteLedgerFiles(!loadOnly); err != nil {
-			reportWarnf("Error deleting ledger files: %v", err)
+		if delErr := deleteLedgerFiles(!loadOnly); delErr != nil {
+			reportWarnf("Error deleting ledger files: %v", delErr)
 		}
 	}()
 	defer l.Close()

cmd/goal/account.go

@@ -948,16 +948,16 @@ No --delete-input flag specified, exiting without installing key.`)
 			reportErrorf(errorRequestFail, err)
 		}
 		// In an abundance of caution, check for ourselves that the key has been installed.
-		if err := client.VerifyParticipationKey(time.Minute, addResponse.PartId); err != nil {
-			err = fmt.Errorf("unable to verify key installation. Verify key installation with 'goal account partkeyinfo' and delete '%s', or retry the command. Error: %w", partKeyFile, err)
-			reportErrorf(errorRequestFail, err)
+		if vErr := client.VerifyParticipationKey(time.Minute, addResponse.PartId); vErr != nil {
+			vErr = fmt.Errorf("unable to verify key installation. Verify key installation with 'goal account partkeyinfo' and delete '%s', or retry the command. Error: %w", partKeyFile, vErr)
+			reportErrorf(errorRequestFail, vErr)
 		}
 
 		reportInfof("Participation key installed successfully, Participation ID: %s\n", addResponse.PartId)
 
 		// Delete partKeyFile
-		if nil != os.Remove(partKeyFile) {
-			reportErrorf("An error occurred while removing the partkey file, please delete it manually: %s", err)
+		if osErr := os.Remove(partKeyFile); osErr != nil {
+			reportErrorf("An error occurred while removing the partkey file, please delete it manually: %s", osErr)
 		}
 	},
 }

cmd/goal/application.go

@@ -484,14 +484,14 @@ var createAppCmd = &cobra.Command{
 		if outFilename == "" {
 			// Broadcast
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			reportInfof("Attempting to create app (approval size %d, hash %v; clear size %d, hash %v)", len(approvalProg), crypto.HashObj(logic.Program(approvalProg)), len(clearProg), crypto.HashObj(logic.Program(clearProg)))
@@ -559,23 +559,23 @@ var updateAppCmd = &cobra.Command{
 		// Broadcast or write transaction to file
 		if outFilename == "" {
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			reportInfof("Attempting to update app (approval size %d, hash %v; clear size %d, hash %v)", len(approvalProg), crypto.HashObj(logic.Program(approvalProg)), len(clearProg), crypto.HashObj(logic.Program(clearProg)))
 			reportInfof("Issued transaction from account %s, txid %s (fee %d)", tx.Sender, txid, tx.Fee.Raw)
 
 			if !noWaitAfterSend {
-				_, err = waitForCommit(client, txid, lv)
-				if err != nil {
-					reportErrorf(err.Error())
+				_, err2 = waitForCommit(client, txid, lv)
+				if err2 != nil {
+					reportErrorf(err2.Error())
 				}
 			}
 		} else {
@@ -629,23 +629,23 @@ var optInAppCmd = &cobra.Command{
 		// Broadcast or write transaction to file
 		if outFilename == "" {
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			// Report tx details to user
 			reportInfof("Issued transaction from account %s, txid %s (fee %d)", tx.Sender, txid, tx.Fee.Raw)
 
 			if !noWaitAfterSend {
-				_, err = waitForCommit(client, txid, lv)
-				if err != nil {
-					reportErrorf(err.Error())
+				_, err2 = waitForCommit(client, txid, lv)
+				if err2 != nil {
+					reportErrorf(err2.Error())
 				}
 			}
 		} else {
@@ -699,23 +699,23 @@ var closeOutAppCmd = &cobra.Command{
 		// Broadcast or write transaction to file
 		if outFilename == "" {
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			// Report tx details to user
 			reportInfof("Issued transaction from account %s, txid %s (fee %d)", tx.Sender, txid, tx.Fee.Raw)
 
 			if !noWaitAfterSend {
-				_, err = waitForCommit(client, txid, lv)
-				if err != nil {
-					reportErrorf(err.Error())
+				_, err2 = waitForCommit(client, txid, lv)
+				if err2 != nil {
+					reportErrorf(err2.Error())
 				}
 			}
 		} else {
@@ -769,23 +769,23 @@ var clearAppCmd = &cobra.Command{
 		// Broadcast or write transaction to file
 		if outFilename == "" {
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			// Report tx details to user
 			reportInfof("Issued transaction from account %s, txid %s (fee %d)", tx.Sender, txid, tx.Fee.Raw)
 
 			if !noWaitAfterSend {
-				_, err = waitForCommit(client, txid, lv)
-				if err != nil {
-					reportErrorf(err.Error())
+				_, err2 = waitForCommit(client, txid, lv)
+				if err2 != nil {
+					reportErrorf(err2.Error())
 				}
 			}
 		} else {
@@ -839,23 +839,23 @@ var callAppCmd = &cobra.Command{
 		// Broadcast or write transaction to file
 		if outFilename == "" {
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			// Report tx details to user
 			reportInfof("Issued transaction from account %s, txid %s (fee %d)", tx.Sender, txid, tx.Fee.Raw)
 
 			if !noWaitAfterSend {
-				_, err = waitForCommit(client, txid, lv)
-				if err != nil {
-					reportErrorf(err.Error())
+				_, err2 = waitForCommit(client, txid, lv)
+				if err2 != nil {
+					reportErrorf(err2.Error())
 				}
 			}
 		} else {
@@ -909,23 +909,23 @@ var deleteAppCmd = &cobra.Command{
 		// Broadcast or write transaction to file
 		if outFilename == "" {
 			wh, pw := ensureWalletHandleMaybePassword(dataDir, walletName, true)
-			signedTxn, err := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, err2 := client.SignTransactionWithWalletAndSigner(wh, pw, signerAddress, tx)
+			if err2 != nil {
+				reportErrorf(errorSigningTX, err2)
 			}
 
-			txid, err := client.BroadcastTransaction(signedTxn)
-			if err != nil {
-				reportErrorf(errorBroadcastingTX, err)
+			txid, err2 := client.BroadcastTransaction(signedTxn)
+			if err2 != nil {
+				reportErrorf(errorBroadcastingTX, err2)
 			}
 
 			// Report tx details to user
 			reportInfof("Issued transaction from account %s, txid %s (fee %d)", tx.Sender, txid, tx.Fee.Raw)
 
 			if !noWaitAfterSend {
-				_, err = waitForCommit(client, txid, lv)
-				if err != nil {
-					reportErrorf(err.Error())
+				_, err2 = waitForCommit(client, txid, lv)
+				if err2 != nil {
+					reportErrorf(err2.Error())
 				}
 			}
 		} else {
@@ -1314,9 +1314,9 @@ var methodAppCmd = &cobra.Command{
 
 		var retType *abi.Type
 		if retTypeStr != abi.VoidReturnType {
-			theRetType, err := abi.TypeOf(retTypeStr)
-			if err != nil {
-				reportErrorf("cannot cast %s to abi type: %v", retTypeStr, err)
+			theRetType, typeErr := abi.TypeOf(retTypeStr)
+			if typeErr != nil {
+				reportErrorf("cannot cast %s to abi type: %v", retTypeStr, typeErr)
 			}
 			retType = &theRetType
 		}
@@ -1405,9 +1405,9 @@ var methodAppCmd = &cobra.Command{
 		txnGroup = append(txnGroup, appCallTxn)
 		if len(txnGroup) > 1 {
 			// Only if transaction arguments are present, assign group ID
-			groupID, err := client.GroupID(txnGroup)
-			if err != nil {
-				reportErrorf("Cannot assign transaction group ID: %s", err)
+			groupID, gidErr := client.GroupID(txnGroup)
+			if gidErr != nil {
+				reportErrorf("Cannot assign transaction group ID: %s", gidErr)
 			}
 			for i := range txnGroup {
 				txnGroup[i].Group = groupID
@@ -1432,9 +1432,9 @@ var methodAppCmd = &cobra.Command{
 				continue
 			}
 
-			signedTxn, err := createSignedTransaction(client, shouldSign, dataDir, walletName, unsignedTxn, txnFromArgs.AuthAddr)
-			if err != nil {
-				reportErrorf(errorSigningTX, err)
+			signedTxn, signErr := createSignedTransaction(client, shouldSign, dataDir, walletName, unsignedTxn, txnFromArgs.AuthAddr)
+			if signErr != nil {
+				reportErrorf(errorSigningTX, signErr)
 			}
 
 			signedTxnGroup = append(signedTxnGroup, signedTxn)