feat: add terminal width support to StringWriteStream
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StringWriteStreamStringWriteStream
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Thanks. Does this mean we need to implement a specific interface that advertises columns? Who gets to take advantage of this?
| constructor() { | ||
| super(); | ||
| // Read terminal width from stdout to enable proper table formatting | ||
| this.columns = process.stdout.columns; |
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Should probably be a getter, because the column count can change over time.
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@rix0rrr Thanks for the quick review! I've added some more information to the Context and Consequences sections in the PR description. |
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Adds terminal width detection to StringWriteStream to enable proper table formatting that respects terminal width constraints and prevents overflow. The columns getter dynamically reads from process.stdout.columns, allowing it to reflect runtime changes such as terminal resizing. Returns undefined in non-TTY environments (e.g., CI/CD pipelines). Includes comprehensive unit tests with 100% coverage covering: - Core stream functionality (writing, buffering, conversion) - Terminal width initialization and handling - TTY and non-TTY environment support - Multiple terminal width scenarios - Dynamic terminal resize handling
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Context
The diff formatting library expects streams to provide an optional
columnsproperty (via theFormatStreaminterface) to enable terminal width-aware table formatting. StringWriteStream currently lacks this property, causing the diff formatter to format tables without width constraints, leading to overflow and poor rendering in different terminal environments.Changes
columnsgetter to StringWriteStream that dynamically reads terminal width fromprocess.stdout.columnsundefinedin non-TTY environments (CI/CD pipelines, redirected output)formatTable()for IAM changes, security group changes, and other table-formatted outputConsequences
The
Formatterclass will automatically use this property when callingformatTable()for IAM changes, security group changes, and other table-formatted outputConsiderations
The
columnsgetter reads fromprocess.stdout.columnson every access, ensuring it always reflects the current terminal width. This design allows the stream to respond to terminal resize events without requiring additional event listeners or manual updates. The diff formatter will automatically pick up this property through the existingFormatStreaminterface.Now, there's no guarantee that people will output the text collected in the
StringWriteStreamto stdout, but that is my use case. 🤷By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license