gotools/go/types/typeutil/imports.go

// Dependencies returns all dependencies of the specified packages.
//
// Dependent packages appear in topological order: if package P imports
// package Q, Q appears earlier than P in the result.
// The algorithm follows import statements in the order they
// appear in the source code, so the result is a total order.
func Dependencies(pkgs ...*types.Package) []*types.Package { … }