Struct RenderFanInMetric 

pub struct RenderFanInMetric {
    pub per_component: Vec<RenderFanInComponent>,
    pub p95_distinct_parents: Option<u32>,
    pub high_pct: Option<f64>,
    pub max_distinct_parents: Option<u32>,
}

Per-component render fan-in counts plus the precomputed concentration aggregates.

DESCRIPTIVE blast-radius signal (NOT a rule, finding, or threshold): the component-graph analogue of module-level fan-in. Module fan-in counts importing MODULES; render fan-in counts JSX render CALL SITES (a shared <Button> is rendered in far more places than it is imported).

per_component is the internal carrier (keyed for hotspot path annotation), #[serde(skip)] on AnalysisResults so it never appears under bare fallow / audit; the aggregates feed the descriptive VitalSigns block (p95_render_fan_in / render_fan_in_high_pct / max_render_fan_in).

UNDERCOUNT is the documented safe direction: a child rendered via a JSX spread, a dynamic / createElement(var) form, or a member-expression tag (<Lib.Button/>) is not resolved by the shared ChildResolver and so increments no component’s fan-in. A true high-fan-in component can only be undersold, never falsely flagged. A rare name-collision over-credit is possible via the default-import sole-component fallback (inherited verbatim from the prop-drilling / thin-wrapper resolver); low-harm for a descriptive, non-gating metric.

Fields

per_component: Vec<RenderFanInComponent>

Per-component render-site + distinct-parent counts. Keyed by (component file path, component name) so the hotspot surface can map a file back to its top component’s fan-in. Components rendered nowhere ARE included as a real 0 so the percentile distribution is not skewed.

p95_distinct_parents: Option<u32>

95th-percentile DISTINCT-PARENTS render fan-in across components (the per-component distribution analogue of the module-fan-in p95). None on an empty population. Mirrors compute_coupling_concentration.

high_pct: Option<f64>

Percentage of components whose distinct-parents render fan-in exceeds the max(p95, 10) threshold (the same floor coupling concentration uses). None on an empty population.

max_distinct_parents: Option<u32>

The single highest DISTINCT-PARENTS count across all components (the headline blast-radius number: the most distinct render LOCATIONS any one component is rendered from, the honest edit-ripple count). None on an empty population. render_sites (incl. repeats) is secondary per-component context, never the headline.

Trait Implementations

impl Clone for RenderFanInMetric

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RenderFanInMetric

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for RenderFanInMetric

fn default() -> Self

Returns the “default value” for a type.