Add information on running tests (#796)

Co-authored-by: SpyCheese <[email protected]>

README.md

@@ -70,4 +70,4 @@ If a CI workflow fails not because of your changes but workflow issues, try to f
 
 ## Running tests
 
-Tests are executed by running `ctest` in the build directory.
+Tests are executed by running `ctest` in the build directory. See `doc/Tests.md` for more information.

doc/Tests.md

@@ -0,0 +1,24 @@
+# Tests execution
+TON contains multiple unit-tests, that facilitate detection of erroneous blockchain behaviour on each commit.
+## Build tests
+Go inside the build directory and, if you use ninja, build the tests using the following command:
+
+```ninja test-ed25519 test-ed25519-crypto test-bigint test-vm test-fift test-cells test-smartcont test-net test-tdactor test-tdutils test-tonlib-offline test-adnl test-dht test-rldp test-rldp2 test-catchain test-fec test-tddb test-db test-validator-session-state```
+
+For more details on how to build TON artifacts, please refer to any of Github actions.
+
+For cmake use:
+
+```cmake --build . --target test-ed25519 test-ed25519-crypto test-bigint test-vm test-fift test-cells test-smartcont test-net test-tdactor test-tdutils test-tonlib-offline test-adnl test-dht test-rldp test-rldp2 test-catchain test-fec test-tddb test-db test-validator-session-state```
+
+## Run tests
+Go inside the build directory and with ninja execute:
+
+```ninja test```
+
+with ctest:
+
+```ctest```
+
+## Integration of tests into CI
+Most relevant GitHub actions include the step ```Run tests``` that executes the tests. If any of tests fails, the action will be interrupted and no artifacts will be provided.