[gantt-dependencies] Dependency lines not connected to tasks

[Eifi1]

Specification ID

gantt-dependencies

Affected Libraries

• matplotlib
• seaborn
• plotly
• bokeh
• altair
• plotnine
• pygal
• highcharts
• letsplot

Category

None

Description

What's wrong; The supposed to be connection lines are somewhere in the plot seemingly unrelated to the displayed tasks.

Expected: Connection lines at the end of one task to the beginning of a next dependent one.

[github-actions]

❌ Validation Failed

The AI validation workflow encountered an error. A maintainer will review this manually.

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🤖 report-validate

[claude]

Report Analysis

Specification: gantt-dependencies
Target: Implementation (plotly)
Category: Visual

Problem Summary

The dependency connector lines are positioned incorrectly and appear disconnected from the task bars they should be linking. Lines should connect from the end of a predecessor task to the start of the dependent task, but they appear at seemingly random positions in the plot instead.

Analysis

This is a valid issue. The root cause is a coordinate system mismatch in the implementation code. The dependency lines are drawn using Plotly shapes with numeric y-coordinates (y0=pred_idx, y1=curr_idx as integer indices), while the actual task bars use a categorical y-axis with task names. Plotly shapes reference numeric positions (0, 1, 2, etc.) which don't align with the categorical axis positions rendered on the chart.

The AI review notes also flagged this: "Y-axis index-based referencing for shapes may cause alignment issues with categorical axis" (listed as a weakness in the quality review).

To fix this, the shapes should either:

1. Use yref="y" with categorical values (task names) instead of numeric indices, or
2. Use a different approach such as annotation arrows with categorical references

Recommended Action

• Spec update needed: No - the specification correctly describes the expected behavior
• Regeneration needed: Yes - plotly implementation needs to be regenerated with proper coordinate handling for dependency lines

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Next: Add approved label when ready to fix.