`stellar contract extend` panics with "index out of bounds" when the extension is a no-op

[leighmcculloch]

What version are you using?

soroban-cli 26.1.0 (installed via Homebrew). The offending code is also present on main.

What did you do?

Ran stellar contract extend against a well-formed but non-existent contract ID. The transaction goes through as a no-op, then the CLI panics:

$ stellar contract extend --id CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABSC4 --ledgers-to-extend 1
ℹ️ Simulating transaction…
ℹ️ Signing transaction: decde71f91ef2ce9d89a56fb2d9d4a2725b6034e6efc853a73e924d5d7130313
🌎 Sending transaction…
✅ Transaction submitted successfully!
🔗 https://stellar.expert/explorer/testnet/tx/decde71f91ef2ce9d89a56fb2d9d4a2725b6034e6efc853a73e924d5d7130313
ℹ️ No changes detected, transaction was a no-op.

thread 'main' (12110178) panicked at /Users/brew/Library/Caches/Homebrew/cargo_cache/registry/src/index.crates.io-1949cf8c6b5b557f/soroban-cli-26.1.0/src/commands/contract/extend.rs:288:42:
index out of bounds: the len is 0 but the index is 0
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
❌

The same crash occurs when attempting to extend any entry that doesn't exist.

What did you expect to see?

A clean error or message indicating the entry does not exist / nothing was extended, with a non-panic exit.

What did you see instead?

The CLI panicked with index out of bounds: the len is 0 but the index is 0 at src/commands/contract/extend.rs:288:42 and exited with a failure code.