diff --git a/tests/cli/validation.test.js b/tests/cli/validation.test.js
index f1947cd92..02c5d9e95 100644
--- a/tests/cli/validation.test.js
+++ b/tests/cli/validation.test.js
@@ -197,4 +197,13 @@ describe('Validation', () => {
       exitCode: 1,
     },
   )
+
+  cliTest(
+    'Block handler with incompatible mapping function',
+    ['codegen', '--skip-migrations'],
+    'validation/block-handler-with-incompatible-mapping-function',
+    {
+      exitCode: 1,
+    },
+  )
 })
diff --git a/tests/cli/validation/block-handler-with-incompatible-mapping-function.stderr b/tests/cli/validation/block-handler-with-incompatible-mapping-function.stderr
new file mode 100644
index 000000000..34cafba50
--- /dev/null
+++ b/tests/cli/validation/block-handler-with-incompatible-mapping-function.stderr
@@ -0,0 +1,7 @@
+- Load subgraph from subgraph.yaml
+✖ Failed to load subgraph from subgraph.yaml: Error in subgraph.yaml:
+
+  Path: dataSources > 0 > blockHandlers > 0
+  Matching mapping handler not found in './mapping.ts' for blockHandler: 'handleBlock'.
+  Signature:
+    handleBlock(block: ethereum.BlockWithTransactions): void
diff --git a/tests/cli/validation/block-handler-with-incompatible-mapping-function/Abi.json b/tests/cli/validation/block-handler-with-incompatible-mapping-function/Abi.json
new file mode 100644
index 000000000..4d05f5839
--- /dev/null
+++ b/tests/cli/validation/block-handler-with-incompatible-mapping-function/Abi.json
@@ -0,0 +1,7 @@
+[
+  {
+    "type": "event",
+    "name": "ExampleEvent",
+    "inputs": [{ "type": "string" }]
+  }
+]
diff --git a/tests/cli/validation/block-handler-with-incompatible-mapping-function/mapping.ts b/tests/cli/validation/block-handler-with-incompatible-mapping-function/mapping.ts
new file mode 100644
index 000000000..55376e559
--- /dev/null
+++ b/tests/cli/validation/block-handler-with-incompatible-mapping-function/mapping.ts
@@ -0,0 +1,9 @@
+import { ethereum } from '@graphprotocol/graph-ts'
+import { ExampleBlockEntity } from './generated/schema'
+
+export function handleBlock(block: ethereum.BlockWithReceipts): void {
+  let entity = new ExampleBlockEntity(block.hash.toHexString())
+  entity.number = block.number
+  entity.hash = block.hash
+  entity.save()
+}
\ No newline at end of file
diff --git a/tests/cli/validation/block-handler-with-incompatible-mapping-function/schema.graphql b/tests/cli/validation/block-handler-with-incompatible-mapping-function/schema.graphql
new file mode 100644
index 000000000..96ba50b79
--- /dev/null
+++ b/tests/cli/validation/block-handler-with-incompatible-mapping-function/schema.graphql
@@ -0,0 +1,5 @@
+type ExampleBlockEntity @entity {
+  id: ID!
+  number: BigInt!
+  hash: Bytes!
+}
diff --git a/tests/cli/validation/block-handler-with-incompatible-mapping-function/subgraph.yaml b/tests/cli/validation/block-handler-with-incompatible-mapping-function/subgraph.yaml
new file mode 100644
index 000000000..66d422fe0
--- /dev/null
+++ b/tests/cli/validation/block-handler-with-incompatible-mapping-function/subgraph.yaml
@@ -0,0 +1,22 @@
+specVersion: 0.0.1
+schema:
+  file: ./schema.graphql
+dataSources:
+- kind: ethereum/contract
+  name: ExampleSubgraph
+  network: mainnet
+  source:
+    abi: ExampleContract
+  mapping:
+    kind: ethereum/events
+    apiVersion: 0.0.1
+    language: wasm/assemblyscript
+    file: ./mapping.ts
+    entities:
+    - ExampleBlockEntity
+    abis:
+    - name: ExampleContract
+      file: ./Abi.json
+    blockHandlers:
+    - handler: handleBlock
+      blockFormat: block-with-transactions
\ No newline at end of file